Electric vacuum cleaner provided with a dust separation section for separating sucked dust and dust collecting section for collecting the dust

ABSTRACT

A dust separation section is provided at a suction air passage between a suction opening of a vacuum cleaner main body and an intake opening of a motor fan to separate dust sucked from the suction opening with air and a dust collection section provided at the suction air passage for collecting the dust separated from the air from the dust separation section. Moreover, the dust separation section of the electric vacuum cleaner has a dust guiding space adapted to inflow the dust sucked from the suction opening from one end of the dust guiding space and for guiding the dust from an other end of the dust guiding space to the dust collection section, through a dust strike section, by an inertia force, and an air guiding air passage is provided to guide air from a midstream of the dust guiding space to the intake opening of the motor fan without passing through the dust collection section.

This application is a U.S. National Phase Application under 35 USC 371of International Application PCT/JP2003/003253 filed Mar. 18, 2003.

TECHNICAL FIELD

The present invention relates to an electric vacuum cleaner providedwith a dust separation section for separating sucked dust and a dustcollection section for collecting the dust.

BACKGROUND ART

Heretofore, there have been known an electric vacuum cleaner providedwith a cyclone system as shown in FIG. 34 (for example, see JapanesePatent Laid Open No. 2001-104223).

The electric vacuum cleaner is provided with a dust cup 1 whose upperpart is opened and a motor fan 2 for causing inside of the dust cup 1 tobe negatively pressured or the like. An intake vent 3 is formed at aperipheral wall 1A of the dust cup 1 and the intake vent 3 iscommunicated with a suction opening body 4 for sucking a dust through anintake passage 5.

The dust sucked from the suction opening body 4 is sucked inside of thedust cup 1 from the intake vent 3 of the dust cup 1 through the intakepassage 5. A spiral flow is generated inside of the dust cup 1, therebythe dust and air are separated, and only the air is sucked from theupper part opening of the dust cup 1 by the motor fan 2 and is exhaustedoutside.

By the way, in such electric vacuum cleaner, the air sucked upwardlytoward the intake passage 5 changes direction at 90 degrees and entersinside of the dust cup 1 from the intake vent 3, and at this point, theair is turned into the spiral flow and adapted to be revolved along theperipheral wall 1A of the dust cup 1 and then only the air is suckedupwardly toward the motor fan 2. Like so, because the direction of theair is changed twice, its loss of air passage is large (i.e., loss in anamount of air passing through is large), and furthermore, because theair is sucked to the motor fan 2 after revolving inside of the dust cup1, its loss of air passage becomes exceedingly large, causing a problemthat a performance of the motor fan deteriorates.

Additionally, there have been also known such a conventional electricvacuum cleaner that allows the dust which is sucked inside of a dustcollection case to be separated by hitting the dust to a hyperbolic wallsection as disclosed in Japanese Patent Publication No. 61-22563 forexample.

In this electric vacuum cleaner, there is provided a cylindrical dustcollection case that extends toward upward and downward direction, and amain body case which is loaded on a top edge of the dust collectioncase. Inside of the main body, the motor fan is built-in for causing asucking-negative pressure to operate in the dust collection case.

Furthermore, in a bottom of the dust collection case, a longitudinalwall is provided which projects upwardly from a part proximity to anedge of a bottom wall. At a center of the longitudinal wall, there isformed a helical groove disengaging in an upward direction. Also, at thelongitudinal wall, a partition wall is continuously built to divideinside of the dust collection case into lower side's first dustcollection room and upper side's second dust collection room by markingoff inside of the dust collection case into an upper part and a lowerpart.

The partition wall has a bottom plate whose edge has a U-shape and isalso provided with a projecting portion that engages to a lower end ofthe helical groove of the longitudinal wall, an internal side wall whichis continuously built to both sides edge of the helical grooverespectively and is also built projective toward an upward direction ata part proximity to side edge in a U-shape along the side edge of thebottom plate, and a hyperbolic external side wall which is formed with ahyperbolic shape at an edge of the bottom plate corresponding to theU-shaped part of the internal wall and is also positioned opposite tothe longitudinal wall. Further, at the hyperbolic part of the internalside wall, there is formed an opening, and between the internal sidewall and the hyperbolic external side wall, there is formed a hyperbolicair passage.

Also, a ventilation opening is formed between the hyperbolic externalwall and the longitudinal wall, and a mesh shaped filter is loaded tothe ventilation opening. In addition, the hyperbolic external side wallis provided as a primary filter at the opposite side of the side wall'slongitudinal wall in such a manner as to extend in upward and downwarddirection and roughly concentric to the dust collection case, and a hoseopening is provided at the dust collection case facing the hyperbolicexternal side wall. Moreover, in this electric vacuum cleaner, an upperend of the dust collection case is closed with a filter holding plate,and at the filter holding plate, there is formed a tube sectionconnected to an upper part of a hyperbolic internal side wall, and amain filter is loaded to a lower end of the tube section.

In such an electric vacuum cleaner as mentioned, when the motor fan isactivated, the motor fan's sucking negative pressure acts upon the firstdust collection room through the main filter, the second dust collectionroom and the mesh shaped filter, and the intake negative pressure thatacts upon the first dust collection room acts upon the suction openingbody which is not shown in the figure through dust collection hose andextension pipe for example that are connected to a hose connectionopening.

By the aforementioned method, the dust sucked from the suction openingbody is sucked to the first dust collection room with the air from thehose opening through the dust collection hose. And, some of the suckeddust and the air hit hyperbolic external side wall and then, flow alongthe hyperbolic external wall toward a side of the mesh shape filter. Onthis occasion, relatively heavy dust is adapted to be dropped anddeposited on a bottom of a rough dust room, and remained dust's lightcotton dust, for example, is captured by the mesh shaped filter when theair percolates the mesh shaped filter.

Furthermore, microscopic dust even smaller than the cotton dust passesthrough the mesh shaped filter together with the air. Such microscopicdust is captured through the main filter when the air passes through themain filter, and is deposited on a bottom of the second dust collectionroom.

But, in fact, because the air that hits the hyperbolic external sidewall flows toward the side of the mesh shaped filter along thehyperbolic external side wall, the dust flows toward the side of themesh shape filter along the hyperbolic external side wall together withthe air.

In addition, relatively large and heavy dust is adapted to be depositedat a lower part of the mesh shape filter. Consequently, if an amount ofdust deposited increases, then the amount of deposited dust increases atthe side of the mesh shaped filter before the dust is captured in entirerough dust room, causing a tendency that the filter clogs at an earlystage.

Also, because some of the air hits the hyperbolic external wall flows tothe lower part along the hyperbolic external wall, the dust that hitsthe hyperbolic wall and drops to the lower part flows to the side of thelongitudinal wall together with the air that flows to the lower part,causing some of the dust deposited on the side of the longitudinal wallto fly up, so there is a tendency that the dust flew up attaches to themesh shaped filter and the mesh shaped filter clogs at an early stage.

The reason that these phenomena occurs is because all the air that aresucked from the hose connection opening are adapted to flow only to thefirst dust collection room which is to capture the dust, then adapted toflow to side of the second dust collection room through the ventilationopenings' mesh shape filter which opens at the first collection room.

In addition, there is also a conventional electric vacuum cleaner in atype that loads a paper package as a paper filter at the dust collectionroom. In this common electric vacuum cleaner, since the intake vent, thepaper package and the motor fan are arranged linearly, the loss of airpassage is relatively small. However, in such common electric vacuumcleaner there is a problem that an amount of air decreases significantlyonce the dust accumulates in the paper package.

It is an object of the invention to provide an electric vacuum cleanerwhich is capable of reducing the loss of air passage, and furthermore,in which the amount of air does not decrease at the early stage even ifthe dust accumulates.

DISCLOSURE OF INVENTION

An electric vacuum cleaner of the present invention has a dustseparation section provided at a suction air passage which is leadingfrom a suction opening of a vacuum cleaner main body to an intakeopening of a motor fan to separate dust sucked from the suction openingwith air and a dust collection section provided at the suction airpassage for collecting the dust separated from the air at the dustseparation section.

In addition, the dust separation section has a dust guiding spaceadapted to inflow the dust sucked from the suction opening from an oneend and for guiding the dust which flows in from an other end to thedust collection section by an inertia force. Also, an air guiding airpassage is provided in the electric vacuum cleaner of the presentinvention to be communicated with a midstream of the dust guiding ductand is communicated with the intake opening of the motor fan withoutpassing through the dust collection section.

According to the structure mentioned above, since the dust sucked withthe air goes straight by inertia and is collected, and the air is suckedby the motor fan through the opening, the air and the dust are separatedwithout generating the spiral flow, therefore loss of air passagebecomes less.

Additionally, the dust guiding space can be provided as a tubularpassage which an one end communicates with the suction opening so thatthe dust sucked from the suction opening flows in and an other endcommunicates with the dust collection section. Moreover, it is possibleto provide an air guiding opening provided at a peripheral wall of thetubular passage and communicate with the intake opening of the motorfan.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a perspective view schematically showing an externalappearance of an electric vacuum cleaner relating to the presentinvention.

FIG. 2 is a perspective view showing a vacuum cleaner main body of theelectric vacuum cleaner shown in FIG. 1.

FIG. 3 is a partial sectional side view showing the vacuum cleaner mainbody shown in FIG. 2.

FIG. 4 is a side view showing a condition that a lid body is opened.

FIG. 5 is a perspective view showing the vacuum cleaner main body in acondition that the lid body is opened and a dust collection case isunloaded.

FIG. 6 is a vertical sectional view showing a structure of the dustcollection case.

FIG. 7 is a perspective view showing the dust collection case.

FIG. 8 is a partial horizontal sectional view showing a part of the dustcollection case.

FIG. 9 is an explanatory view showing a principle of the presentinvention.

FIG. 10 is a partial sectional side view showing the vacuum cleaner mainbody of the electric vacuum cleaner of the other embodiment of thepresent invention.

FIG. 11 is an enlarged sectional view showing the dust collection casein FIG. 10.

FIG. 12 is a perspective diagram viewing the dust collection case inFIG. 11 from oblique-rear side.

FIG. 13 is an explanatory view showing a part of the dust collectioncase in FIG. 11 in a horizontal sectional view and also showing a partof a net filter by enlarging.

FIG. 14 is a partial sectional side view showing the vacuum cleaner mainbody of the electric vacuum cleaner of still other embodiment of thepresent invention.

FIG. 15 is a partial horizontal sectional view showing the dustcollection case and a tubular filter in FIG. 14.

FIG. 16 is a partial sectional side view showing the vacuum cleaner mainbody of the electric vacuum cleaner of still other embodiment of thepresent invention.

FIG. 17( a) is an enlarged sectional view showing the dust collectioncase in FIG. 10.

FIG. 17( b) is a sectional view taken along an A-A line in FIG. 17( a).

FIG. 18 is an explanatory view showing a part of a mesh shaped netfilter in FIGS. 16 and 17 by enlarging.

FIG. 19 is an enlarged sectional view showing the dust collection caseof still other embodiment of the present invention.

FIG. 20 is a partial sectional side view showing the vacuum cleaner mainbody of the electric vacuum cleaner of still other embodiment of thepresent invention.

FIG. 21 is an explanatory view showing the dust collection case in FIG.20 by enlarging and also showing a relationship of arrangement between amotor fan.

FIG. 22 is a disassembled perspective view showing the dust collectioncase in FIG. 21 and a filter which is fixed to a rear opening of thedust collection case by disassembling them.

FIG. 23 is a horizontal sectional view showing the dust collection case,the tubular filter and the filter of the rear opening in FIG. 21.

FIG. 24 is a sectional view of the tubular filter of still otherembodiment of the present invention.

FIG. 25 is an operational-explanatory view of the tubular filter shownin FIG. 24.

FIG. 26 is a perspective view schematically showing an externalappearance of the electric vacuum cleaner of still other embodiment ofthe present invention.

FIG. 27 is an enlarged side view of the vacuum cleaner main body in FIG.26.

FIG. 28 is a side view of the vacuum cleaner main body in a conditionthat the lid body in FIG. 27 is opened.

FIG. 29 is a partial sectional side view of the vacuum cleaner shown inFIG. 27.

FIG. 30 is a side view of the dust collection case in FIG. 29.

FIG. 31 is a sectional view schematically showing a cross section of thedust collection case in FIG. 29 and a part which guides a dust to a dustcollection room.

FIG. 32 is a horizontal sectional view showing the dust collection casein FIG. 31 and the tubular filter.

FIG. 33 is an explanatory view showing a condition that the lid body ofthe dust collection case in FIG. 31 is opened.

FIG. 34 is a sectional view showing one example of a conventionalelectric vacuum cleaner.

BEST MODE FOR CARRYING OUT THE INVENTION

[Principle of the Invention]

Hereinafter embodiments of the present invention will be described withreference to the accompanying drawings.

First, a principle of the present invention will be described brieflywith reference to FIG. 9.

In FIG. 9, 100 is a suction opening (intake vent) for sucking dust in avacuum cleaner main body. A dust separation section 101 is providedbetween the suction opening 100 and a motor fan 107. 107A is an intakeopening of the motor fan.

The dust separation section 101 has a tube section 102 which is forminga tubular passage 102S that extends linearly and its cross-sectionalarea is constant, and a strike section 103 which is continuously builtto an other side opening 102A of the tube section 102. The strikesection 103 is communicated with the tube section 102 and is composed ofa pipe section that protrudes to a lower direction.

103A is a wall of the strike section 103, and the wall 103A is adaptedto be faced to the other side opening 102A. And substantially, the wall103A is a dust strike section.

A dust collection room 104 is formed at a lower part of the strikesection 103. The dust collection room 104 and the tube section 102 arecommunicated through the strike section 103 which is more specifically,the pipe section. Additionally, the suction opening 100, the tubesection 102 and the motor fan 107 are arranged in alignment. Also, oneend opening 102B of the tube section 102 is communicated with thesuction opening 100.

A plurality of openings 102H are formed at a peripheral wall of the tubesection 102. In addition, the dust separation section 101 is coveredwith a case 105. The motor fan 107 is loaded to the case 105, and theinside of the case 105 is adapted to be negatively pressured by themotor fan 107.

Once the inside of the case 105 becomes the negative pressure by anactivation of the motor fan 107, the negative pressure acts upon thepassage (tubular air passage) 102S which is in the tube section 102through the openings 102H of the tube section 102, and the dust issucked together with air from the suction opening 100. The air and thedust that are sucked from the suction opening 100 go straight throughthe passage 102S within the tube section 102, and the air is, on theway, sucked inside of the case 105 through the openings 102H. The suckedair is sucked from the intake opening 107A by the motor fan 107.Normally, a filter for capturing microscopic dust is arranged in frontof the intake opening 107A.

On the other hand, the dust which has more weight than predeterminedweight goes straight inside of the passage 102S of the tube section 102by inertia without change, and after hitting the wall 103A of the strikesection 103, falls to the dust collection room 104 through a pipesection which composes the strike section 103, and it becomesaccumulated (deposited) at the dust collection room 104.

As mentioned above, because the dust and the air are separated in thepassage 102S without generation of a spiral flow, a loss of air passagein the passage 102S becomes less. Furthermore, as the suction opening100, the tube section 102 and the motor fan 107 are arranged inalignment, the air that is sucked to the opening 107A flows virtuallylinearly and sucked by the motor fan 107 without changing its directionof the airflow significantly as shown by an arrow P. Consequently, sincean overall loss of air passage becomes even less (i.e., overall loss inan amount of air passing through is less), performance of the motor fan107 is improved.

In this principle, although the plurality of openings 102H are providedat the pipe section 102, it may be also recommendable to provide asingle opening 102H. In addition, the strike section 103 is notnecessarily required to separate the dust from the air by an inertiaforce.

As described above, in this electric vacuum cleaner of the presentinvention of such principle, the dust separation section 101 is providedat a suction air passage leading from the suction opening 100 of thevacuum cleaner main body to the intake opening 107A of the motor fan 107to separate the dust that sucked from the suction opening 100 with theair and the dust collection section (dust collection room 104) providedat the suction air passage for collecting the dust separated from theair at the dust separation section 101. In addition, the dust separationsection 101 has the tubular passage (passage 102S) which communicates atone end with the suction opening 100 to flow the dust sucked from thesuction opening 100 in the tubular passage and at the other end with thedust collection section (dust collection room 104) and the air guidingopening (102H) which is provided at the peripheral wall of the tubularpassage (102S) and which is communicated with the intake opening 107A ofthe motor fan 107.

Generally in the conventional electric vacuum cleaner of the cyclonetype, since the air is, after swirled, reversed, drifted and sucked,therefore the loss of air passage of the air is large. Also in theconventional electric vacuum cleaner with the paper package as the paperfilter, when a predetermined amount of dust is accumulated in the paperpackage, the amount of air decreases easily. On the contrary, in theelectric vacuum cleaner of the present embodiment, because the dustsucked with the air goes straight by the inertia and is collected, andthe air is sucked by the motor fan (107) through an air guiding opening(opening 102H), the air and the dust are separated without generatingspiral flow, therefore the loss of air passage becomes less.

Additionally, in this electric vacuum cleaner of the present inventionof such principle, the dust separation section 101 is provided at thesuction air passage which is leading from the suction opening 100 of thevacuum cleaner main body to the intake opening 107A of the motor fan 107to separate the dust sucked from the suction opening 100 with the airand the dust collection section (dust collection room 104) provided atthe suction air passage for collecting the dust separated from the airat the dust separation section 101. Moreover, the dust separationsection 101 has a dust guiding duct (passage 102S) for inflowing thedust sucked from the suction opening 100 from one end of the duct andfor guiding the dust that inflows from an other end to the dustcollection section (dust collection room 104) by the inertia force.Still moreover, an air passage for guiding air (air passage from theplurality of openings 102H to the intake opening 107A of the motor fan107) is provided to be communicated with a midstream of the dust guidingduct (passage 102S) and is communicated with the intake opening 107A ofthe motor fan 107 without passing through the dust collection section(dust collection room 104).

As well as in this electric vacuum cleaner, as the dust sucked with theair goes straight by inertia and is collected, and the air is sucked bythe motor fan (107) through the air guiding opening (opening 102H), theair and the dust are separated without generating spiral flow, thereforethe loss of air passage becomes less. By the way, in the principle ofthe present invention, although the dust guiding duct is formed in thelinear shaped pipe section 102, it is not necessarily limited to this.For example, the tube section 102 which the dust guiding duct is formedmay also be shaped such that the diameter of the tube section 102gradually decreases while going to a direction of a downstream ofairflow, or on the contrary, in such a shape that expands its diameteras going to a direction of the downstream of airflow, or its crosssection is square or polygon in shape. Also, it may also berecommendable to provide the tube section 102 with an inertia applyingpipe section for applying a direct advancing inertia force to the dustand a dust guiding pipe section for guiding the dust which is goingstraight to a dust collection section (dust collection room 104). Inthis instance, it may also be recommendable that the inertia applyingpipe section and the dust collection section are separated as long asthe inertia applying pipe section and the dust guiding pipe section areprovided concentrically and a diameter of the dust guiding pipe sectionis formed larger enough than a diameter of the inertia applying pipesection.

More additionally, in this electric vacuum cleaner of the presentinvention of such principle, the dust separation section 101 is providedat the suction air passage leading from the suction opening 100 of thevacuum cleaner main body to the intake opening 107A of the motor fan 107to separate the dust sucked from the suction opening 100 with the airand the dust collection section (dust collection room 104) provided atthe suction air passage for collecting the dust separated from the airat the dust separation section 101. Furthermore, the dust separationsection 101 has the tubular passage (passage 102S) as a dust guiding airpassage (dust inflow air passage) which at one end is communicated withthe suction opening 100 and adapted to flow in the dust sucked from thesuction opening 100, and an air guiding air passage provided with theair guiding opening (102H) which is provided on the peripheral wall ofthe passage (102S) at one end, and at the other end is communicated withthe intake opening 107A of the motor fan 107 without passing through thedust collection section (dust collection room 104).

As well as in this electric vacuum cleaner, as the dust sucked with theair goes straight by the inertia and is collected, and the air is suckedby the motor fan (107) through the air guiding opening (opening 102H),the air and the dust are separated without generating the spiral flow,therefore the loss of air passage becomes less.

[Mode for Carrying Out the Invention 1]

Next, embodiments of an electric vacuum cleaner applied with abovementioned principle of the invention will be described with reference tothe accompanying drawings.

In FIG. 1, 20 is a vacuum cleaner main body, and one end of a hose 21 isconnected attachably and detachably to the vacuum cleaner main body 20and a hand operating pipe 22 is provided on the other end. An extensionpipe 23 is connected attachably and detachably to the hand operatingpipe 22 and a suction opening body 24 is connected to the end of theextension pipe 23 attachably and detachably. Also, a control section 22Ais provided on the hand operating pipe 22, and there is provided on thecontrol section 22A a control switch which is not shown.

As shown in FIGS. 2 to 5, the vacuum cleaner main body 20 is providedwith a main body case 30 and a dust collection case (dust cup, dustcollection container) 50 which is attachably and detachably mounted onthe main body case 30 and a lid body 40 capable of opening and closingin upward and downward directions, that a back end is connected to themain body case 30 by a hinge connection.

The main body case 30 has a motor-driven section 34 which is a rear casesection loaded with a motor fan 33. At a lower part of front side of themotor-driven section 34, there is provided a mounting section 35 whichis in a plate-shape that protrudes to a forward direction. Onto themounting section 35, the dust collection case 50 is attachably anddetachably mounted. Furthermore, the dust collection case 50 is adaptedto be fixed by holding of the lid body 40 and the mounting section 35when the lid body 40 is closed.

Also, a front side of the motor-driven section 34, that is, a front sideof the rear case section has opening 34A which is provided with a frame34 b in a radial pattern for retaining a filter. The opening 34A facesan intake opening 33A of the motor fan 33 and are communicated.

At both side faces of the main body case 30, an expanded section 36 isformed throughout an upper part of a front side and to a lower part of aback side. A rear wheel 37 is retained at a lower part of the expandedsection 36 which is capable of revolving freely. Additionally, at afront side of both side faces of the expanded section 36 and the mainbody case 30, a plurality of exhaust holes 38 are formed. These exhaustholes 38 are communicated with an exhaust opening 33B of the motor fan33 through an exhaust air passage which is not shown. By this, the airthat is exhausted from the exhaust opening 33B of the motor fan 33 isexhausted outside from the exhaust hole 38 through the exhaust airpassage. Also, in the motor-driven section 34 of the main body case 30,a battery which is not shown is contained at a lower part of the motorfan 33.

The lid body 40 has a top panel 41 which is formed virtually ellipticalin shape if seen in flatways, and a peripheral wall 42 is integrallyformed at a perimeter of the top panel 41. At a front part of thisperipheral wall 42, a connection pipe 44 which has a connection opening(suction opening) 43 for attachably and detachably connecting the dustcollection hose 21 is provided. The connection pipe 44 extends in alongitudinal direction, and a back end 45 of it is opened.

With respect to FIGS. 6 to 8, the dust collection case 50 has acontainer case body 53 (shown in FIG. 7) which has an opening 51 on arear face (right side in FIG. 6) and a suction opening (air inflowopening) 52 at a front face, and a handle section 54 which is integrallyformed at below the suction opening 52 of the container case body 53.

The container case body 53 has a dust collection room section (dustcollection section) 55 formed at a lower part, a negative pressure roomsection 56 as an air guiding air passage formed above the dustcollection room section 55, a dust separation section 60 provided withinthe negative pressure room section 56 and a guide pipe 70 for guidingthe dust separated at the dust separation section 60 to the dustcollection room section 55. In addition, the container case body 53 hasa front wall 53 a and the suction opening 52 is formed at a side of anupper part of the front wall 53 a.

At a bottom of the dust collection room section 55, a bottom plate 57 isattached capable of opening and closing about an axis J, and it is madecapable of throwing away the dust accumulated in the dust collectionroom section 55 by opening the bottom plate 57. A ventilation opening 59as an exhaust opening (ventilation aperture) is formed at a top panel 58of the dust collection room section 55 which divides the dust collectionroom section 55 and the negative pressure room section 56. Theventilation opening 59 is closed by a net filter (exhaust filter) F1that is attached to the ventilation opening 59.

A connection hole 58A is formed behind the ventilation opening 59 of thetop panel 58. At lower part of the connection hole 58A, there isprovided a guide wall G to generate spiral flow at inside of the dustcollection room section 55.

The dust separation section 60 has a tubular filter 62 which forms atubular passage (flow passage, or more specifically, the air passage)61, and a strike section 63 which is provided at an other end opening62B of the tubular filter 62. A diameter of one end opening 62A of thetubular filter 62 is formed larger than a diameter of the suctionopening 52. The one end opening 62A of the tubular filter 62 and thesuction opening 52 of the container case body 53 are connected so as thesuction opening 52 to be located at an inner side. A diameter of theother end opening 62B of the tubular filter 62 is set virtuallysimilarly as the diameter of its suction opening 52, and a diameter ofthe tubular filter 62 decreases gradually as going from one end to theother end linearly. That is to say, the tubular filter 62 of the dustseparation section 60 is adapted to have a reducing diameter which is ina circular cone shape (taper shape) as gradually going to the downstreamdirection of the air passage. By the way, it may be recommendable to setthe diameter of the other end opening 62B of the tubular filter 62smaller than the diameter of the suction opening 52.

The passage 61 of the tubular filter 62 extends linearly to alongitudinal direction. The connection pipe 44 of the lid body 40, thesuction opening 52 of the container case body 53, the tubular filter 62,the opening 51 of the container case body 53 and the intake opening 33Aof the motor fan 33 are arranged in alignment.

As shown in FIG. 6, the tubular filter 62 has a tubular frame(equivalent to the tube section 102 indicated in the principle of theinvention) W which is provided with a plurality of openings 64 as an airguiding opening, and a net filter (mesh shape filter) F2 which is in amesh shape attached to an inner peripheral side of the tubular frame W.The tubular frame W also has a frame section W1 in a circular shape(round shape) forming the one end opening 62A, a frame section W2 whichis in a round shape and a tubular shape (circular shape) forming theother end opening 62B, and a plurality of frame sections W3 (rib shapedframe section) which are in a rib shape that connect the frame sectionsW1 and W2. By the way, the spaces surrounded by each frame sectionsW1-W3 are the openings (air guiding opening) 64. The openings 64 as anair guiding opening are equally provided throughout entire circumferenceof the tubular filter 62. In addition, the passage 61 is formed andsurrounded by the frame sections W1-W3 and the net filter F2. In FIG. 7,indication of the net filter F2 shown in FIG. 6 has been omitted as amatter of convenience to describe the openings 64.

Furthermore, the net filter F2 is formed in a tubular shape along theinner periphery of the tubular frame W as a filter tube section, and isattached to the tubular frame W by adhesion or fusion bonding forexample in such a manner as to cover the plurality of openings 64.Moreover, a metallic coating layer formed on a surface of a mesh shaperesin fiber by sputtering is used for the net filter F2, therefore thenet filter F2 is made to provide extremely easy slippage so as to avoidan attachment of the dust.

The passage 61 of the tubular filter 62 is communicated with the intakeopening 33A of the motor fan 33 through the openings 64 of the tubularfilter 62, the negative pressure room section 56 of the container casebody 53 and the opening 34A of the motor-driven section 34 of the mainbody case 30. Also, the extending directions of the passage 61 of thetubular filter 62 and the connection pipe 44 of the lid body 40 are inalignment, and the intake opening 33A of the motor fan 33 faces towardthe extending of direction the passage 61 of the tubular filter 62.

The strike section 63 has a slant wall section 63A extending from anupper side of the other end opening 62B of the tubular filter 62 to alower side on a slant, and a strike wall section 63B which faces to theother end opening 62B of the tubular filter 62 and is also incurved fromone end of the slant wall section 63A and extending to a lower part, anda side wall section 63C which is formed at both sides of the slant wallsection 63A and the strike wall section 63B. Additionally, the strikesection 63 has an opening 63D jointed to the other end opening 62B ofthe tubular filter 62 and also has an opening 63E which faces to a lowerpart.

The guide pipe 70 extends in a vertical direction, and is communicatedwith inside of the dust collection room section 55 through the opening63E of the strike section 63 and the connection hole 58A of the toppanel 58.

Further, there is fitted a filter 80 at the opening 51 of the containercase body 53 to capture the microscopic dust failed to be captured bythe net filters F1 and F2. Furthermore, the filter 80 is pressed andattached by the motor-driven section, that is, by a frame 34 b which isprovided at the front surface of the rear case section.

[Operation]

Next, an operation of the electric vacuum cleaner constituted as abovewill be described.

First, as shown in FIG. 4, the dust collection case 50 is mounted on themounting section 35 of the main body case 30 and then the lid body 40 isclosed, and the hose 21 is connected to the connection opening 43 of thelid body 40. When controlling the switch (not shown) of the controlsection 22A, the motor fan 23 actuates. By the actuation of the motorfan 23, the negative pressure room section 56 of the container case body53 becomes the negative pressure through the opening 34A of the mainbody case 30. This negative pressure acts upon the openings 64 of thetubular filter 62, the passage 61 of the tubular filter 62, the suctionopening 52 of the container case body 53, the connection pipe 44 of thelid body 40, the hose 21, the extension pipe 23 and the suction openingbody 24, thereby the dust on a cleaning surface is sucked together withthe air from the suction opening body 24.

The sucked dust and air are adapted to be sucked to the connectionopening 43 of lid body 40 through the extension pipe 23 and the hose 21.The dust and the air that are sucked to the connection opening 43 areadapted to be sucked to the passage 61 of the tubular filter 62 of thedust separation section 60 through the suction opening 52 of the dustcollection case 50.

Some of the air sucked to the passage 61 passes through the net filterF2 of the openings 64 of the tubular filter 62, and sucked to thenegative pressure room section 56 of the container case body 53, andfurthermore, passes through the filter 80 loaded at the opening 51 ofthe container case body 53 and sucked by the intake opening 33A of themotor fan 33. At this time, the microscopic dust that passed through thenet filter F2 is captured by the filter 80.

On the other hand, because the passage 61 extends linearly to thelongitudinal direction, the dust which is sucked to the passage 61 ofthe tubular filter 62 and which has more weight than predeterminedweight goes straight through the passage 61 and hits the strike wallsection 63B of the strike section 63, and is adapted to be introducedinside of the dust collection room section 55 by the guide pipe 70. Thatis to say, the dust and the air are separated by the dust separationsection 60.

Also, some of the air is adapted to be introduced inside of the dustcollection room section 55 through the strike section 63 and the guidepipe 70, and the introduced air turns into spiral flow by the guide wallG of the dust collection room section 55, and the dust introduced insideof the dust collection room section 55 is accumulated as it iscompressed by the spiral flow.

The air introduced into the dust collection room section 55 is, whenturned into spiral flow, passes through the ventilation opening 59 ofthe top panel 58 of the dust collection room section 55 and the netfilter F1, and is sucked to the negative pressure room section 56 of thecontainer case body 53. At this time, the microscopic dust which haspassed through the net filter F1 is sucked together with the air to thenegative pressure room section 56. In addition, the air sucked to thenegative pressure room section 56 is further sucked by the intakeopening 33A of the motor fan 33 through the filter 80 which is loaded atthe opening 51 of the container case body 53. At this time, themicroscopic dust which passed through the net filter F1 is captured bythe filter 80.

In this way, the air that is exhausted through the openings 64 and theair that is exhausted through the ventilation opening 59 are convergedtogether at the negative pressure room section 56. Further, theconverged air is adapted to be sucked by the intake opening 33A of themotor fan 33 through the filter 80 which is loaded at the opening 51 ofthe container case body 53. As stated above, the microscopic dust whichpassed through the net filters F1 and F2 is captured by the filter 80 atthis time.

By the way, light weighted microscopic dust in the dust which is suckedto the passage 61 of the tubular filter 62 attaches to the net filter F2since it flows with the air that passes the net filter F2 of theopenings 64 without going straight through the passage 61 of the tubularfilter 62. If clogging of the net filter F2 caused by the attachment ofthe microscopic dust becomes larger, the amount of wind that goesthrough the net filter F2 reduces, but the negative pressure of thenegative pressure room section 56 of the container case body 53increases corresponding to the amount it reduced as well as the negativepressure within the dust collection room section 55 through theventilation opening 59 of the top panel 58. Consequently, a windvelocity of the air that goes straight through the passage 61 of thetubular filter 62 becomes greater, therefore the amount of wind whichgoes straight increases.

When the wind velocity that goes straight through the passage 61 of thetubular filter 62 becomes greater, the air that goes straight forwardpeels off the dust attached to the net filter F2. On this occasion,because the diameter of the tubular filter 62 gradually decreases asgoing linearly to the side of the opening 62B, the wind that goesstraight through the passage 61 becomes easier to hit the entire side ofthe net filter F2, therefore the dust attached to the net filter F2 iseasily peeled off.

The peeled dust is adapted to be introduced and accumulated in the dustcollection room section 55 through the strike section 63 and the guidepipe 70.

Also, even if the amount of wind that passes through the net filter F2is reduced by clogging, the amount of wind the motor fan 33 sucks can bemaintained constant because the amount of wind goes straight through thepassage 61 of the tubular filter 62 increases. Consequently, it isalways possible to suck the dust by a predetermined sucking power withirrespective of clogging of the net filter F2.

Additionally, by a fact that the dust and the air are not separated bygeneration of spiral flow within the passage 61 of the tubular filter62, the loss of air passage within the passage 61 becomes less.Furthermore, when the air sucked from the passage 61 of the tubularfilter 62 to the negative pressure room section 56 of the container casebody 53 through the net filter F2, the flowing direction of air does notchange significantly as shown by the arrow Q (see FIG. 3), because thesuction opening 52, the tubular filter 62, the opening 51 of thecontainer case body 53 and the intake opening 33A of the motor fan 33are arranged in alignment, therefore flows virtually linearly to themotor fan 33 to be sucked.

Consequently, the loss of air passage becomes even less (i.e., loss inan amount of air passing through becomes even less), so that theperformance of the motor fan 33 can be achieved sufficiently. Further,because the connection pipe 44 of the lid body 40 and the tubular filter62 are arranged in a straight line, a direction of the air introduced tothe suction opening 52 of the container case body 53 becomes inalignment with the extending direction of the tubular filter 62,therefore its loss of air passage becomes even more less.

Moreover, by providing the dust collection room section 55 below thedust separation section 60 and by providing the ventilation opening 59at the top panel 58 of the dust collection room section 55, theventilation opening 59 which communicates the dust collection roomsection 55 and the negative pressure room section 56 penetrates the toppanel 58 in a vertical direction. By this structure, the dust attachedto the net filter F1 which is fixed to the ventilation opening 59 fallsto a lower part by its own weight and is accumulated inside of the dustcollection room section 55. Also, the clogging is hard to occur sincethe dust attached to the net filter F1 can be removed easily, thereforethe deterioration in sucking efficiency can be avoided.

According to the present invention as described above, it is possible toreduce the loss of air passage, and even amount of wind at the suctionopening does not decrease even if the dust accumulates, therefore it isalways possible to suck the dust by a predetermined sucking power.

[Mode for Carrying Out the Invention 2]

FIGS. 10-13 show an electric vacuum cleaner corresponding to the secondembodiment of the present invention. The same reference numbersindicated in FIGS. 1-8 are given for the parts identical or resembles tothe structure of the embodiment shown in FIGS. 1-8, and theirdescriptions are omitted.

The dust separation section 60 in the second embodiment of the presentinvention has, as mentioned above, the tubular filter 62 formed with thepassage 61 which is in a tubular shape and a strike member (tubularbody) provided with the strike section 63 which is set at the other endopening 62B of the tubular filter 62. As shown in FIGS. 10 and 11, adiameter D1 of the one end opening 62A of the tubular filter 62 isformed larger than a diameter d of the suction opening (air inflowopening) 52 of the container case body 53, and a diameter D2 of theother end opening 62B of the tubular filter 62 is formed larger than adiameter of its suction opening 52. That is to say, the diameter d ofthe suction opening (air inflow opening) 52 is formed smaller than thediameter D2 of the other end opening 62B of the tubular filter 62.

When the air containing the dust flows and enters in the tubular filter62 from the suction opening 52, the air containing the dust flows to thedirection of the one end opening 62B from the one end opening 62A of thetubular filter 62, therefore the one end opening 62A of the tubularfilter 62 becomes as an upstream end and the other end opening 62Bbecomes as a downstream end in consideration of the flow of air.Further, the one end opening 62A (upstream end) of the tubular filter 62is closely contacted or fixed to a rear side of the front wall 53 a ofthe container case body 53 at a periphery of the suction opening (airinflow opening) 52. Thereby the suction opening 52 of the container casebody 53 and the one end opening 62A are each connected so as to set thesuction opening 52 at the position which is inside of the one endopening 62A. In addition, the diameter of the one end opening 62A(upstream end) of the tubular filter 62 is formed larger than thediameter of the suction opening 52.

Also, the diameter of the tubular filter 62 gradually decreases as goinglinearly to the other end (downstream end) from the one end (upstreamend). In other words, the diameter of the tubular filter 62 of the dustseparation section 60 is gradually adapted to diminish in a circularcone shape (taper shape) as going to the downstream direction of the airpassage.

Moreover, the passage 61 of the tubular filter 62 extends linearly to alongitudinal direction, and the connection pipe 44 of the lid body 40,the suction opening 52 of the container case body 53, the tubular filter62, the opening 51 of the container case body 53 and the intake opening33A of the motor fan 33 are arranged in alignment.

As shown in FIG. 11, the tubular filter 62 has the tubular frame W whichis provided with the plurality of openings 64, and the net filter (meshshaped filter) F2 which is in a mesh shape attached to an innerperipheral side of the tubular frame W (see FIG. 12). The tubular frameW also has the frame section W1 which is in a circular shape (roundshape) forming the one end opening 62A, the frame section W2 which is ina round shape and a tubular shape (circular shape) forming the other endopening 62B, and the plurality of frame sections W3 (rib shaped framesection) which are in rib shape that connect the frame sections W1 andW2 (see FIGS. 11-13). By the way, the spaces surrounded by each framesections W1-W3 are the openings 64. The openings 64 are equally providedthroughout the entire circumference of the tubular filter 62. Inaddition, the passage 61 is formed and surrounded by the frame sectionsW1-W3 and the net filter F2.

Also, the net filter F2 is formed in a tubular shape along the innerperiphery of the tubular frame W as the filter tube section, and isattached to the tubular frame W by adhesion or fusion bonding forexample in such a manner as to cover the plurality of openings 64.

Additionally, in the tubular frame W, the diameter D1 of the upstreamend is formed larger than the diameter d of the suction opening (airinflow opening) 52 and the diameter D2 of the downstream end is formedlarger than the diameter d of the suction opening (air inflow opening)52. In other words, the diameter d of the suction opening (air inflowopening) 52 is formed smaller than the diameter D2 of the downstream end(other end opening 62B) of the tubular frame W. Also, the suctionopening 52, the one end opening 62A and the other end opening 62B areprovided substantially concentric.

Furthermore, a metallic coating layer formed on the surface of the meshshape resin fiber by the sputtering is used for the net filter F2,thereby the net filter F2 is made to provide extremely easy slippage soas to avoid attachment of the dust.

Moreover, as shown in FIG. 13, if a coarseness of a mesh (opening) Ma ofthe net filter F2 of the tubular filter 62 is S1, more specifically, ifa dimension of an opening of mesh (net) is S1, and if the coarseness ofa mesh (opening) Mb of the net filter F2 attached to the ventilationopening 59 which is an exhaust opening is S2, more specifically, if adimension of an opening of mesh (net) is S2, then the dimension of themesh opening S1 of the net filter F2 is formed smaller than thedimension of the mesh opening S2 of the net filter F1 (exhaust filter).

Also, if an amount of wind of the air that passes through the tubularfilter 62 and inflows (sucked) to the negative pressure room section 56is Q1, and if an amount of wind of the air that inflows (sucked) to thenegative pressure room section 56 through the ventilation opening 59which is as the exhaust opening and the net filter F1 is Q2, then theamount of wind of the air Q1 that passes through the net filter F2 ofthe tubular filter 62 is set less than the amount of wind of the air Q2that passes through the net filter F1 of the dust collection roomsection (dust collection section) 55. That is to say, the amount of windQ2 is set larger than the amount of wind Q1.

A relation between the wind amounts Q1 and Q2 is determined throughvarious conditions such as a sucking performance of the motor fan 33,the coarseness of mesh of the net filters F1 and F2 (size of the opening(opening) of mesh) and cross-sectional area or length of each airpassages. But the relation between the wind amounts Q1 and Q2 can bechanged by the coarseness (size of the opening of mesh) of mesh of thenet filters F1 and F2 as long as the conditions other than the netfilters F2 and F2 are determined and are constant.

In addition, the passage 61 of the tubular filter 62 is communicatedwith the intake opening 33A of the motor fan 33 through the openings 64of the tubular filter 62, the negative pressure room section 56 of thecontainer case body 53 and the opening 34A of the motor-driven section34 of the main body case 30. Also, the extending directions of thepassage 61 of the tubular filter 62 and the connection pipe 44 of thelid body 40 are in alignment, and the intake opening 33A of the motorfan 33 faces toward the extending direction of the passage 61 of thetubular filter 62.

The strike section 63 has the slant wall section 63A extending from theupper side of the other end opening 62B of the tubular filter 62 to thelower side on a slant, and the strike wall section 63B which faces tothe other end opening 62B of the tubular filter 62 and which is alsoincurved from the one end of the slant wall section 63A and extending tothe lower part, and the side wall section 63C formed at both sides ofthe slant wall section 63A and the strike wall section 63B.Additionally, the strike section 63 has an opening 63D jointed to theother end opening 62B of the tubular filter 62 and also has an opening63E which faces the lower part.

The strike section 63 is provided at upper part of the guide pipe 70which is separately formed to the tubular filter 62 as shown in FIGS. 11and 12. The guide pipe 70 extends in a vertical direction and iscommunicated with inside of the dust collection room section 55 throughthe opening 63E of the strike section 63 and the connection hole 58A ofthe top panel 58.

By the way, it may be recommendable to form the tubular filter 62, thestrike section 63 and the guide pipe 70 integrally and form separatelyfrom the container case body 53, and fix to the top panel 58 of the dustcollection room section 55 of the container case body 53 by adhesion orsupersonic fusion bonding. Also, it may be recommendable to form thestrike section 63 and the guide pipe 70 integrally and form separatelyfrom the tubular filter 62 and the container case body 53, and fix thetubular filter 62 to the strike section 63 and the front wall 53 a byadhesion or supersonic fusion bonding together with fix a lower end ofthe guide pipe 70 to the top panel 58 by adhesion or supersonic fusionbonding.

[Operation]

Next, an operation of the electric vacuum cleaner constituted as abovewill be described hereinafter.

As mentioned above, the dust on a cleaning surface is sucked with theair inside of the tube shaped passage 61 by operating the motor fan 33.Some of the air sucked to the passage 61 (particularly a peripheral airof the airflow that flows into the passage 61) passes through the netfilter F2 of the openings 64 of the tubular filter 62 and sucked to thenegative pressure room section 56 of the container case body 53, andfurther sucked by the intake opening 33A of the motor fan 33 through thefilter 80 loaded at the opening 51 of the container case body 53. Onthis occasion, the microscopic dust which passed through the net filterF2 is captured by the filter 80.

Meanwhile, because the passage 61 extends linearly to the longitudinaldirection, the dust which is sucked to the passage 61 of the tubularfilter 62 and which has more weight than predetermined weight and theremaining air (air) go straight through the passage 61 and hit thestrike wall section 63B of the strike section 63.

At this time, in the dust that inflows with an atmospheric air (air)from the suction opening 52 into the passage 61, although the light dustis in some of the air which is at a side of the net filter F2, the otherair goes virtually straight forward by the inertia force. Since thelight dust is relatively light in weight, the inertia energy is less.The dust that goes straight forward is relatively heavy in weight andtherefore the inertia energy is large.

Therefore, within the dust that inflows from the suction opening 52,when the dust that goes virtually straight forward by the inertia forcecaused when flowing into the passage 61 from the suction opening 52 hitsthe downstream end part of the net filter (filter tube section) F2, thedust breaks into the mesh (mesh opening) of the downstream end part ofthe filter F2 by the inertia energy, thereby the downstream end part ofthe net filter F2 clogs and a permeability loses, as a result, arecovery in the permeability cannot be expected.

But in the present embodiment, since a vast majority of dust that flowsinto the passage 61 from the suction opening 52 and also the dust at theperiphery part go straight forward by the inertia energy, and inaddition, since the diameter d of the suction opening 52 is formedsmaller than the diameter D2 of the opening 62B which is the downstreamend of the tubular filter 62, the dust that goes virtually straightforward by the inertia force caused when flowing into the passage 61from the suction opening 52 hits the strike wall section 63B of thestrike section 63 without hitting the downstream end of the filter F2.Therefore, clogging at the downstream end of the net filter (filter tubesection) F2 caused by the dust flowing into the passage 61 from thesuction opening 52 and going straight forward can be avoided. On thisoccasion, the remaining air that goes straight without passing throughthe net filter F2 also hits the strike wall section 63B of the strikesection 63.

In addition, the dust struck the strike wall section 63B and theremaining air which goes straight without passing through the filter F2are biased to a lower direction and then adapted to be introduced insideof the dust collection room section 55 by the guide pipe 70. Asdescribed, some of the air and the dust are separated by the dustseparation section 60, and the separated dust and the remaining air areadapted to be introduced inside of the dust collection room section 55by the guide pipe 70.

The air that is introduced inside of the dust collection room section 55becomes spiral flow by the guide wall G of the dust collection roomsection 55, and accumulates the dust on a bottom side of the dustcollection room section 55 while compressing the dust which isintroduced inside of the dust collection room section 55. Later, the airpasses through the ventilation opening 59 of the top panel 58 of thedust collection room section 55 and the net filter F1, and is sucked tothe negative pressure room section 56 of the container case body 53.

On this occasion, the microscopic dust which passed through the netfilter F1 is sucked together with the air to the negative pressure roomsection 56. In addition, the air that is sucked to the negative pressureroom section 56 is furthermore sucked by the intake opening 33A of themotor fan 33 through the filter 80 which is loaded at the opening 51 ofthe container case body 53. The microscopic dust that passed through thenet filter F1 is captured by the filter 80 at this time.

In this manner, the air exhausted through the openings 64, and the airexhausted through the ventilation opening 59 are converged together atthe negative pressure room section 56. Further, the converged air issucked by the intake opening 33A of the motor fan 33 through the filter80 which is loaded at the opening 51 of the container case body 53. Asstated above, the microscopic dust which passed through the net filtersF1 and F2 is captured by the filter 80.

In addition, the amount of wind of the air Q1 that passes through thenet filter F2 as mentioned above is set less than the amount of wind ofthe air Q2 that is sucked inside of the negative pressure room section56 through the guide pipe 70, the dust collection room section 55 andthe opening (exhaust opening). Consequently, the vast majority of thedust flowing into the tubular filter 12 from the suction opening 52flows the passage 61 in the tubular filter 62 linearly toward the strikewall section 63B of the strike section 63. Therefore, a separation rateof the dust at inside of the tubular filter 62 increases, that is,within the dust flowing into the tubular filter 62, a proportion offlowing toward the strike wall section 63B without flowing to the sideof the net filter F2 of the tubular filter 62 increases. This separationrate increases more as the amount of wind Q2 becomes larger to theamount of wind Q1.

Furthermore, the light weighted microscopic dust attaches to the netfilter F2 since it flows with the air that passes the net filter F2 ofthe openings 64 without going straight through the passage 61 of thetubular filter 62. If the clogging of the net filter F2 caused by theattachment of the microscopic dust becomes larger, the amount of windthat goes through the net filter F2 reduces, but the negative pressureof the negative pressure room section 56 of the container case body 53increases corresponding to the amount it reduced as well as the negativepressure within the dust collection room section 55 through theventilation opening 59 of the top panel 58. Consequently, the windvelocity of the air that goes straight through the passage 61 of thetubular filter 62 becomes greater, therefore the amount of wind whichgoes straight increases. When the wind velocity that goes straightthrough the passage 61 of the tubular filter 62 become greater, the airthat goes straight peels off the dust attached to the net filter 62.

By the way, the mesh opening (coarseness) S1 of mesh of the net filterF2 of the tubular filter 62 is set smaller than the mesh opening(coarseness) S2 of mesh the net filter F1. Consequently, the powerincreases, that is to say, the amount of wind sucking the dust to thedust collection room section 55 increases, therefore, the net filter F2becomes hard to be clogged.

In addition, even if the amount of wind that passes through the netfilter F2 is reduced by clogging, the amount of wind that the motor fan33 sucks can be maintained constantly, because the amount of wind thatgoes straight through the passage 61 of the tubular filter 62 increases.Consequently, it is always possible to suck the dust by a predeterminedsucking power irrespective of the clogging of the net filter F2.

Also, by the fact that the dust and the air are not separated bygeneration of spiral flow within the passage 61 of the tubular filter62, the loss of air passage within the passage 61 becomes less.Furthermore, when the air is sucked from the passage 61 of the tubularfilter 62 to the negative pressure room section 56 of the container casebody 53 through the net filter F2, the flowing direction of air does notchange significantly as shown by the arrow Q (see FIG. 3), since thesuction opening 52, the tubular filter 62, the opening 51 of thecontainer case body 53 and the intake opening 33A of the motor fan 33are arranged in alignment, therefore it flows virtually linearly to themotor fan 33 to be sucked.

Consequently, the loss of air passage becomes even less, as a result,the performance of the motor fan 33 can be achieved sufficiently.Further, because the connection pipe 44 of the lid body 40 and thetubular filter 62 are arranged in a straight line, the direction of theair introduced to the suction opening 52 of the container case body 53becomes in alignment with the tubular filter 62, therefore its loss ofair passage (i.e., loss of an amount of air passing through) becomeseven lesser.

As described above, the electric vacuum cleaner in the second embodimentof the present invention is comprised of the dust separation section 60which is provided at the suction air passage leading from the suctionopening 52 of the vacuum cleaner main body 20 to the intake vent (intakeopening 33A) for separating the dust from the air sucked from thesuction opening, and the dust collection section (dust collection roomsection 55) provided at the suction air passage for capture and collectthe dust that are separated from the air at the dust separation section60. Furthermore, the dust separation section 60 has the tubular filter62, and the cross-sectional area of the air inflow opening (the suctionopening 52 of the present embodiment acts as both the suction openingfor the vacuum cleaner main body and the air inflow opening to thetubular filter 62) which compared to the tubular filter 62 is smallerthan the cross-sectional area of the air exhaust end (the other endopening 62B) which is to the tubular filter 62. This relation is set bysetting the diameter d of the suction opening 52 so as to become smallerthan the diameter D2 of the other end opening 62B of the tubular filter62, in the present embodiment.

According to the above mentioned structure, the dust that goessubstantially straight by the inertia force caused when flowing from thesuction opening 52 into the passage 61 does not hit the downstream endpart of the tubular filter 62. By this structure, the clogging of thedownstream end part of the net filter (filter tube section) F2 by thedust that flows and goes straight from the suction opening 52 into thepassage 61 can be avoided.

Also, according to the electric vacuum cleaner described in the secondembodiment of the present invention, the dust collection section (dustcollection room section 55) has an exhaust opening (ventilation opening59) which is communicated with the intake vent (intake opening 33A) ofthe motor fan 33. Further, the amount of wind Q1 that passes through thenet filter F2 of the tubular filter 62 (without passing through the dustcollection room section 55) is set less than the amount of wind Q2 thatflows to the intake vent (intake opening 33A) of the motor fan 33through the dust collection section (dust collection room section 55)and the exhaust opening (ventilation opening 59).

According to this structure, the separation rate of the dust inside ofthe tubular filter 62, that is, the ratio of within the dust that flowsinto the tubular filter 62 and that goes straight without flowing to theside of the mesh of the tubular filter 62 increases.

Furthermore, according to the electric vacuum cleaner described in thesecond embodiment of the present invention, a mesh shape filter (netfilter F2) is used for the tubular filter 62, and an exhaust filter (netfilter F1) in a mesh shape is attached to the exhaust opening(ventilation opening 59) and, the dimension of the opening S1 of themesh of the tubular filter 62 is set smaller than the dimension of theopening S2 of mesh of the exhaust filter (net filter F1).

According to this structure, since the power rises, more specifically,since the amount of wind sucking the dust to the dust collection room(dust collection room section 55) becomes larger, the net filter F2becomes hard to clog.

According to the invention as described above, the loss of air passage(i.e., loss in an amount of air passing through) can be made small, andthe amount of wind does not decrease even if the dust accumulates, andthe dust attached to a dust separation means which separates the dustfrom the air can be easily removed.

[Mode for Carrying Out the Invention 3]

FIGS. 14 and 15 show an electric vacuum cleaner corresponding to thethird embodiment of the present invention. The same reference numbersindicated in FIGS. 1-8 are given for the parts identical or resembles tothe composition of the embodiment shown in FIGS. 1-8, and theirdescriptions are omitted.

The dust separation section 60 in the third embodiment of the presentinvention has, as mentioned above, the tubular filter 62 forming thepassage 61 which is in a tubular shape and the strike member (tubularbody) provided with the strike section 63 which is provided at the otherend opening 62B of the tubular filter 62. As shown in FIGS. 14 and 15, adiameter d1 of the one end opening 62A of the tubular filter 62 isformed larger than a diameter d2 of the suction opening (air inflowopening) 52 of the container case body 53, and a diameter d3 of theother end opening 62B of the tubular filter 62 is formed smaller thanthe diameter d2 of its suction opening 52.

Here, when the air containing the dust flows and enters in the tubularfilter 62 from the suction opening 52, the air containing the dust flowsto the direction of the one end opening 62B from the one end opening 62Aof the tubular filter 62, therefore the one end opening 62A of thetubular filter 62 becomes as the upstream end, and the other end opening62B becomes as the downstream end in consideration of the flow of air.In addition, the one end opening 62A (upstream end) of the tubularfilter 62 is closely contacted or fixed to the rear side of the frontwall 53 a of the container case body 53 in a periphery of the suctionopening (air inflow opening) 52. Thereby the suction opening 52 of thecontainer case body 53 and the one end opening 62A are each connected soas to set the suction opening 52 at a position which is inside of theone end opening 62A.

Also, the diameter of the tubular filter 62 gradually decreases as goinglinearly to the other end (downstream end) from the one end (upstreamend). In other words, the diameter of the tubular filter 62 of the dustseparation section 60 is adapted to be gradually diminished in thecircular cone shape (taper tube shape) as going to the downstream end.

Furthermore, the passage 61 of the tubular filter 62 extends linearly inthe longitudinal direction, and the connection pipe 44 of the lid body40, the suction opening 52 of the container case body 53, the tubularfilter 62, the opening 51 of the container case body 53 and the intakeopening 33A of the motor fan 33 are arranged in alignment.

Also, the tubular filter 62 has the tubular frame W which is providedwith the plurality of openings 64 and the net filter (mesh shapedfilter, filter tube section) F2 which is in the tubular shape and in themesh shape that is attached to the inner peripheral side of the tubularframe W. The tubular frame W has the frame section W1 in the circularshape (round shape) which is forming the one end opening 62A, the framesection W2 which is in the round shape and in the tubular shape(circular shape) that is forming the other end opening 62B, and theplurality of frame sections W3 (rib shaped frame section) in a rib shapewhich connect the frame sections W1 and W2. By the way, the spacessurrounded by each frame sections W1-W3 are the openings 64. Theopenings 64 are equally provided throughout the entire circumference ofthe tubular filter 62. In addition, the passage 61 is formed andsurrounded by the frame sections W1-W3 and the net filter F2.

Moreover, the net filter F2 is adapted to be as a filter tube sectionformed in a tubular shape along the inner periphery of the tubular frameW, and is attached to the tubular frame W by adhesion or fusion bondingfor example in such a manner as to cover the plurality of openings 64.Also, the frame section W2 of the tubular frame W is formed in a widerange and is adapted to be a non-mesh tube section. In the frame sectionW2 as the non-mesh tube section, a diameter d4 of the up stream end isformed larger than the diameter d2 of the suction opening (air inflowopening) 52, and the diameter of the downstream end d3 is formed smallerthan the diameter d2 of the suction opening (air inflow opening) 52. Bythis, a periphery of the suction opening 52 corresponds with anintermediate part of the frame section W2 in an air passage direction,and the dust at a periphery within the dust in the air that flows-infrom the suction opening 52 to the passage 61 is adapted to be movedtoward the frame section W2 by the inertia force caused when flowing in.By the way, the suction opening 52, the one end opening 62A and theother end opening 62B are formed substantially concentric.

In the net filter F2, the coarseness of mesh of the mesh shape, that is,the opening of the mesh (net) is formed gradually or step-by-stepsmaller as going from the up stream side to the down stream side of thepassage 61. For example, in the net filter F2, the coarseness of themesh of the mesh shape, that is, the opening of the mesh or net isformed gradually or step by step smaller between 110 μm-30 μm as goingfrom the up stream side to the down stream side of the passage 61.

Furthermore, a metallic coating layer formed on the surface of the meshshape resin fiber by the sputtering is used for the net filter F2,therefore the net filter F2 is made to provide extremely easy slippageso as to avoid the attachment of the dust.

[Operation]

Next, the operation of the electric vacuum cleaner constituted as abovewill be described hereinafter.

As mentioned above, the dust on a cleaning surface is sucked with theair in the passage 61 of the tubular filter 62 of the dust separationsection 60 by activating the motor fan 33. The air that is sucked to thepassage 61 is sucked to the negative pressure room section 56 of thecontainer case body 53 through the net filter F2 of the openings 64 ofthe tubular filter 62, and is further sucked by the intake opening 33Aof the motor fan 33 through the filter 80 loaded at the opening 51 ofthe container case body 53. On this occasion, the microscopic dust whichpassed through the net filter F2 is captured by the filter 80.

Meanwhile, because the passage 61 extends linearly to the longitudinaldirection, the dust that is sucked to the passage 61 of the tubularfilter 62 and has more weight than predetermined weight goes straightthrough the passage 61 and hits to the strike wall section 63B of thestrike section 63.

On this occasion, within the dust that is flown from the suction opening52 and within them at a periphery area, and the dust that goessubstantially straight by the inertia force caused when flowing in fromthe suction opening 52 into the passage 61 has a large inertia energy.Consequently, when the dust that flows in from the suction opening 52and within them at the periphery area and the one that goessubstantially straight by the inertia force caused when flowing into thepassage 61 from the suction opening 52 hits the downstream end part ofthe net filter (filter tube section) F2, the mesh (mesh opening) of thedownstream end part of the filter F2 becomes clogged by the inertiaenergy and thereby permeability loses, and the recovery of thepermeability cannot be expected.

But in the present embodiment, because within the dust that is flownfrom the suction opening 52 and within them at the periphery area, andthe one that goes substantially straight by the inertia force causedwhen flowing into the passage 61 from the suction opening 52 hits thestrike wall section 63B of the strike section 63 after hitting the framesection W2 as the non-mesh section without hitting the downstream endpart of the filter F2, the clogging at the downstream end part of thenet filter (filter tube section) F2 can be reduced. The dust that struckthe strike wall section 63B is introduced inside of the dust collectionroom section 55 by the guide pipe 70. In this manner, the air and thedust are separated by means of the dust separation section 60.

Also, some of the air is adapted to be introduced inside of the dustcollection room section 55 through the strike section 63 and the guidepipe 70, and the introduced air turns to spiral flow by the guide wall Gof the dust collection room section 55, and the dust that is introducedinside of the dust collection room section 55 is adapted to beaccumulated as it is compressed by spiral flow.

The air that is introduced inside of the dust collection room section 55becomes spiral flow by the guide wall G of dust collection room section55, and adapted to accumulate the dust introduced inside of the dustcollection room section 55 to the bottom side of dust collection roomsection 55 as the air compresses the dust. Then, the air percolates theventilation opening 59 of the top panel 58 of the dust collection roomsection 55 and the net filter F1, and sucked to the negative pressureroom section 56 of the container case body 53.

On this occasion, the microscopic dust which passed through the netfilter F1 is sucked together with the air to the negative pressure roomsection 56. In addition, the air that is sucked to the negative pressureroom section 56 is furthermore sucked by the intake opening 33A of themotor fan 33 through the filter 80 which is loaded at the opening 51 ofthe container case body 53. The microscopic dust that passed through thenet filter F1 is captured by the filter 80 at this time.

In this manner, the air exhausted through the openings 64, and the airexhausted through the ventilation opening 59 are converged together atthe negative pressure room section 56. Further, the converged air issucked by the intake opening 33A of the motor fan 33 through the filter80 which is loaded at the opening 51 of the container case body 53. Asstated above, the microscopic dust which passed through the net filtersF1 and F2 is captured by the filter 80.

Because the light weight microscopic dust flows with the air that passesthe net filter F2 of the openings 64 without going straight through thepassage 61 of the tubular filter 62, it attaches to the net filter F2.In addition, if the clogging of the net filter F2 caused by theattachment of the microscopic dust becomes larger, the amount of windthat goes through the net filter F2 reduces, but the negative pressureof the negative pressure room section 56 of the container case body 53increases corresponding to the amount it reduced as well as the negativepressure within the dust collection room section 55 through theventilation opening 59 of the top panel 58. Consequently, the windvelocity of the air going straight through the passage 61 of the tubularfilter 62 becomes greater, and the amount of wind which goes straightincreases. When the wind velocity that goes straight through the passage61 of the tubular filter 62 become greater, the air that goes straightpeels off the dust attached to the net filter F2.

As stated, the wind (air) contains the microscopic and relatively lightdust, and this light dust is adapted to be captured by the net filterF2. It is in such a state that it can easily be peeled off since theinertia energy of the light dust is less and therefore it will not hitthe mesh (net) of the net filter F2 strongly. Also, within the dustcontained in the wind (air), although the dust that is flown from thesuction opening 52 to the passage 61 and within them at the peripheryarea and the one that goes substantially straight by the inertia forcecaused when flowing in from the suction opening 52 into the passage 61has the large inertia energy, this dust hits the wide ranged framesection (non-mesh section) W2 without hitting the net filter F2,therefore the cause for the clogging of the mesh (net) of the net filterF2 can be evaded.

Therefore, when the dust captured by the net filter F2 reaches apredetermined amount, it is peeled off easily from the net filter F2 bythe sucked air that is sucked to the passage 61, and the dust peeledfrom the net filter F2 is adapted to be introduced and accumulated inthe dust collection room section 55 through the strike section 63 andthe guide pipe 70.

Furthermore, because the diameter of the tubular shaped net filter F2 isgradually decreased as going linearly from the upstream end to thedownstream end, the wind that goes to the side of the mesh (net) of thenet filter F2 without going straight through the passage 61 in the netfilter F2 becomes easier to attach entire surfaces of the net filter F2equally. Moreover, this wind (air) contains the relatively light dust,and this light dust hits the entire surfaces of the net filter F2equally and is adapted to be captured by the net filter F2. It is insuch a circumstance that the light dust can easily be peeled off sincethe light dust has the less inertia energy and therefore it will notbreak into the mesh (net) of the net filter F2 strongly.

In addition, even if the amount of wind that passes through the netfilter F2 is reduced by the clogging, the amount of wind that the motorfan 33 sucks can be maintained constantly because the amount of windgoes straight through the passage 61 of the tubular filter 62 increases.Consequently, it is always possible to suck the dust by a predeterminedsucking power regardless of the clogging in the net filter F2.

Also, by the fact that the dust and the air are not separated bygeneration of spiral flow within the passage 61 of the tubular filter62, the loss of air passage (i.e., loss in an amount of air passingthrough) within the passage 61 becomes less. Furthermore, when the airis sucked from the passage 61 of the tubular filter 62 to the negativepressure room section 56 of the container case body 53 through the netfilter F2, the direction of the airflow does not change significantly asshown by the arrow Q (see FIG. 3), because the suction opening 52, thetubular filter 62, the opening 51 of the container case body 53 and theintake opening 33A of the motor fan 33 are arranged in alignment,therefore flows virtually linearly to the motor fan 33 to be sucked.

Consequently, the loss of air passage (i.e., loss in an amount of airpassing through) becomes even less, and the performance of the motor fan33 is improved. Further, because the connection pipe 44 of the lid body40 and the tubular filter 62 are arranged in a straight line, thedirection of the air introduced to the suction opening 52 of thecontainer case body 53 becomes in alignment with the extending directionthe tubular filter 62, therefore its loss of air passage (i.e., loss inan amount of air passing through) becomes evenlesser.

As described above, the electric vacuum cleaner in the third embodimentof the present invention comprises the dust separation section 60provided at the suction air passage leading from the suction opening 52of the vacuum cleaner main body 20 to an intake vent (opening 34A) ofthe motor fan 33 for separating the dust from the air sucked to thesuction opening 52, and the dust collection section (dust collectionroom section 55) provided at the suction air passage for capturing andcollecting the dust separated from the air at the dust separationsection 60. Furthermore, the dust separation section 60 has the filtertube section (net filter F2) in a mesh shape which is located at theupstream side and the non-mesh tube section (frame section W2) which iscommunicated with the lower stream end of the filter tube section (netfilter F2).

According to this structure, the light dust that flows into the filtertube section (net filter F2) is captured by the filter tube section (netfilter F2). It is in such a state that the light dust can easily bepeeled off since the inertia energy of the light dust is less andtherefore it will not break strongly into the mesh (net) of the filtertube section. Also, within the dust contained in the wind (air),although the dust that is flown from the suction opening 52 to thepassage 61 and within them at the periphery area and the one that goessubstantially straight by the inertia force caused when flowing from thesuction opening 52 into the passage 61 which is inside of the filtertube section has the large inertia energy, this dust hits the wideranged non-mesh section (frame section W2) without hitting the netfilter F2, therefore the cause for clogging of the mesh (net) of thefilter tube section (net filter F2) can be evaded.

In the embodiment described above, although the tubular filter 62 andthe filter tube section (net filter F2) are formed in a circular coneshape, that have their diameters which diminish gradually as going tothe direction of the down stream side, it is possible to form thetubular filter 62 and the filter tube section (net filter F2) in thetubular shape which has substantially the same diameter from theupstream end to the downstream end. As well as in this case, when thedust that flows into the filter tube section, and within them at theperiphery part that goes substantially straight hits the downstream endpart of the filter tube section, there is likely to cause that the dustwhich has caused the clogging cannot be peeled off easily by theclogging of the downstream end part of the filter tube section.Therefore, as well as in this case, the cause for the clogging of themesh (net) of the filter tube section (net filter F2) can be evaded assimilar to the filter tube section which is in the circular cone shape,by providing the part where the dust flows into the filter tube sectionand within them at the periphery part that goes substantially straighthits the filter tube section as the non-mesh section.

Also in the third embodiment of the present invention, the dustseparation section 60 is formed in the circular cone shape thatdiminishes its diameter gradually as going to the downstream direction.According to this structure, because the diameter of the filter tubesection (net filter F2) is gradually decreased as going linearly fromthe upstream end to the downstream end, the wind that goes to the sideof the mesh (net) of the filter tube section (net filter F2) withoutgoing straight through the passage 61 in the filter tube section becomeseasier to attach the entire surfaces of the filter tube section (netfilter F2) equally. Moreover, this wind (air) contains the relativelylight dust, and this light dust hits the entire surfaces of the filtertube section (net filter F2) equally and is adapted to be captured bythe net filter F2. It is in such a circumstance that the light dust caneasily be peeled off since the light dust has less inertia energy andtherefore it will not break into the mesh (net) of the net filter F2strongly.

In addition, in the third embodiment of the present invention, thefilter tube section (net filter F2) and the non-mesh tube section (framesection W2) are constituting the tubular filter 62 and the diameter d1of the side of the air inflow opening (one end opening 62A) of thetubular filter 62 is formed larger than the diameter d2 of the airinflow opening (suction opening 52), and the diameter d3 of thedownstream end (other end opening 62B) of the tubular filter 62 isformed smaller in diameter than the diameter d2 of the air inflowopening (suction opening 52) and the diameter d4 of the upstream end ofthe non-mesh tube section (frame section W2) is formed larger than thediameter d2 of the air inflow opening (suction opening 52).

According to this structure, the light dust that flows into the filtertube section (net filter F2) is captured by means of the filter tubesection (net filter F2). It is in such a state that the light dust caneasily be peeled off since the inertia energy of the light dust is lessand therefore it will not break strongly into the mesh (net) of thefilter tube section. Also, within the dust contained in the wind (air),although the dust that is flown from the suction opening 52 to thepassage 61 and within them at the periphery area and the one that goessubstantially straight by the inertia force caused when flowing out fromthe suction opening 52 into the passage 61 which is inside of the filtertube section has the large inertia energy, this dust hits the wideranged non-mesh section (frame section W2) without hitting the netfilter F2, therefore the cause for the clogging of the mesh (net) of thefilter tube section (net filter F2) can be evaded.

As described above, according to this invention, the loss of air passagecan be made small and the amount of wind does not decrease even if thedust accumulates, and the dust attached to the dust separating meanswhich is for separating the dust from the air can be easily removed.

[Mode for Carrying Out the Invention 4]

FIGS. 16-18 show an electric vacuum cleaner corresponding to the thirdembodiment of the present invention. The same reference numbersindicated in FIGS. 1-8 are given for the parts identical or resembles tothe composition of the embodiment shown in FIGS. 1-8, and theirdescriptions are omitted.

As mentioned above, the tubular filter 62 has the frame sections W1 andW2 which are in the round shape, the plurality of frame sections W3 instick shape which connect the frame sections W1 and W2, and the filterF2 in the mesh shape provided at the plurality of openings 64 which areformed by the each frame sections W1-W3 (see FIG. 17( a))

The openings 64 are provided equally throughout the entire circumferenceat the peripheral wall of the passage 61, and the passage 61 is formedand surrounded by the frame sections W3 and the filter F2.

The filter F2 in the mesh shape stands for a filter formed by braidingfine threads in the mesh shape, and a large numbers of threads 100 arebraided in such a manner that are folded mutually as shown in FIG. 18.The filter F2 is formed in the tubular shape in such a manner as tosurround the plurality of openings 64 integrally, and is provided atinner surface of the plurality of frame sections W3 which the framesections W1 and W2 are connected (see FIG. 17( b)).

In addition, an opening O of the filter F2 is formed so that it becomesgradually finer within the range of 110 μm to 30 μm as going from theupstream side of the passage 61 to the downstream side of the passage61, and the coarseness of mesh of the filter F2 becomes gradually finer.In addition, here, the opening O of the filter F2 which is proximity toa part contacted with the frame section W1 is at least 110 μm, and theopening O of the filter F2 which is proximity to a part contacted withthe frame section W2 is 30 μm.

Here, the “upstream side” stands for the side that the air is sucked andflows-in when the motor fan 33 is activated, more specifically, the sideof the suction opening 52 of the container case body 53. The “downstreamside” stands for the side that the air is sucked and flows out when themotor fan 33 is activated, more specifically, the side of the intakeopening 33A of the motor fan 33. Furthermore, the opening O stands forthe mesh aperture, that is, a width between the thread 100 and thethread 100 (see FIG. 18).

Here at, the surface finishing is applied onto the filter F2 forreducing the friction resistance. For the surface finishing, there are,for example, the sputtering process, the fluoric coating and Teflon(registered trademark) coating.

Next, an operation of the electric vacuum cleaner constituted as abovewill be described hereinafter.

As mentioned above, the dust on a cleaning surface is sucked with theair in the passage 61 of the tubular filter 62 of the dust separationsection 60 by activating the motor fan 33. The air sucked to the passage61 is sucked to the negative pressure room section 56 of the containercase body 53 through the net filter F2 of the openings 64 of the tubularfilter 62, and further sucked by the intake opening 33A of the motor fan33 through the filter 80 loaded at the opening 51 of the container casebody 53.

Also, some of the air is adapted to be introduced inside of the dustcollection room section 55 through the strike section 63 and the guidepipe 70, and introduced air turns into spiral flow by the guide wall Gof the dust collection room section 55, then flows into the negativepressure room section 56 through the ventilation opening 59.

On the other hand, the dust that is sucked to the passage 61 of thetubular filter 62 and that has more weight than a predetermined weightgoes straight through the passage 61 by an action of the inertia forcebecause the passage 61 extends linearly to the longitudinal direction,and hits to the strike wall section 63B of the strike section 63, thenintroduced inside of the dust collection room section 55 by the guidepipe 70. Then, the dust introduced inside of the dust collection roomsection 55 is adapted to be accumulated as it is compressed by thespiral flow of the air that likewise flows into the dust collection roomsection 55.

Furthermore, the dust that is microscopic and light in weight sucked tothe passage 61 of the tubular filter 62 flows with the air that passesthe openings 64 without going straight through the passage 61.

As just described, the dust and the air are separated by means of thedust collection room section 60.

Here, as the mesh shaped filter F2 is provided at the openings 64 whichis located at the peripheral wall of the passage 61, even if the dustflows with the air that passes the openings 64, the dust can be capturedby means of the filter F2. In addition, it becomes capable of separatingthe air and the dust efficiently.

Also, even if the dust is lifted into the air again by the spiral flowgenerated when introduced into the dust collection room section 55, theair and the dust are each separated by the net filter F1 provided at theventilation opening 59 and the filter F2 provided at the openings 64,therefore an efficiency in separation can be enhanced.

In addition, as the wind velocity at the upstream side of the passage 61is fast and therefore the dust goes relatively straight, the opening Oof the filter F2 can be created larger. Here, because the opening O isformed in such that it becomes finer as going from the side of thesuction opening 52 as the upstream side of the passage 61 to the side ofthe intake opening 33A as the downstream side of the passage 61, theopening O of the filter F2 is coarse at the side of the suction opening52, therefore the permeability at the side of the suction opening 52 ofthe passage 61 improves and efficiency in suction of air can beimproved.

Meanwhile, it is difficult for the dust to go relatively straight due tothe deterioration in the wind velocity at the side of the intake opening33A which is the downstream side of the passage 61. But in the opening Oof the filter F2, the side of the intake opening 33A of the passage 61is formed fine and can capture the fine dust that flows with the airunfailingly without allowing it to pass. Also, because the opening O isfine and so that a friction is large, therefore the permeability at theside of the intake opening 33A can be suppressed and it is possible tomake the fine dust difficult to flow.

Furthermore, because the opening O of this filter F2 is adapted to befiner as going to the direction from the upstream side of the passage 61to the downstream side, the flow of air passing the passage 61 becomessmoother and the clogging of the filter F2 can be made difficult tooccur.

Like stated, the electric vacuum cleaner in the present invention hasthe dust separation section 60 provided in the air passage which isleading from the suction opening 52 of the vacuum cleaner main body 20to the intake opening 33A of the motor fan 33 for separating the dustfrom the air that are sucked together from the suction opening 52, and adust collection room section (dust collection section) 55 provided inthe air passage for collecting the dust that are separated by the dustseparation section 60. In addition, the dust separation section 60 hasthe one end opening 62A that is communicated with the suction opening 52and the tubular shaped passage (air passage) 61 which the other endopening 62B is communicated with the dust collection room section 55,and the openings 64 which are provided at the peripheral wall of thepassage 61. Furthermore, the mesh shape filter F2 is provided at theopenings 64.

By this structure, it is possible to separate the dust and the airwithout generating spiral flow at inside of the passage 61 of thetubular filter 62 which is the dust separation section 60. Therefore,the separation can be done in efficient manner and the improvement ofseparating efficiency can be made. Also, by this structure, thedeterioration in sucking efficiency can be avoided as the loss of airpassage within the passage 61 becomes small.

Additionally, the fine dust can be captured by the mesh shaped filter F2which is provided at the openings 64 when the dust and the separated airpass from the passage 61 of the tubular filter 62 to the openings 64 andsucked to the negative pressure room section 56 of the container casebody 53.

Furthermore, because the opening O of the filter F2 is made finer asgoing from the upstream side to the downstream side of the passage 61, asufficient permeability can be obtained at the upstream side of passage61 and the deterioration in the sucking efficiency can be avoided. Inaddition, the fine dust can be unfailingly captured at the downstreamside of the passage 61 and it is possible to separate the dust and theair in efficient manner as well as it is possible to separate the dustand the air sufficiently.

Additionally, because the size of the opening O of the filter F2 isformed within the range of 110 μm to 30 μm, the opening O at maximumbecomes 110 μm, therefore it is possible to obtain enough permeabilityin an extent that the dust sucked inside of the passage 61 does notclosely contact with the filter F2. Furthermore, the opening O atminimum becomes 30 μm, therefore it is possible to obtain a necessarypermeability while capable of unfailingly capturing the fine dust whichis flowing with the air, therefore it is possible to improve theseparating efficiency.

Also, because the surface finishing for reducing the friction resistanceis applied on the surface of filter F2, the dust becomes difficult to behooked at the surface of filter F2 and the occurrence of the earlyclogging can be avoided.

Particularly, when the surface finishing is the sputtering process,clogging can be avoided even more as metallic atoms are equally attachedon the surface of filter F2 and the friction resistance can be reducedexceedingly.

By the way, because the filter F2 is provided at the inner surface ofthe frame sections W3, the circumstance that the dust sticks on theframe sections W3 can be avoided, and clogging being difficult to occur.

As described above, according to the electric vacuum cleaner of thepresent invention, it is possible to improve the separating efficiencyby separating the dust and the air efficiently.

[Mode for Carrying Out the Invention 5]

As described above, although one embodiment relating to the presentinvention has been described with reference to the accompanyingdrawings, the present invention is not limited to the specificembodiments as described above, the modifications of design or the likeare included in the present invention without departing from the scopeof the present invention.

For example, in the embodiment mentioned above, although the opening Oof the mesh shaped filter F2 is formed gradually finer as going from thesuction opening 52 side to the intake opening 33A side, it may be alsorecommendable to set the opening O finer in step-by-step way as shown inFIG. 19.

In this instance, for example, at first, separate between the framesection W1 and the frame section W2 with intermediate frame sections W4and W5, and provide a filter F21 which has the opening O of for example,110 μm between the frame section W1 and the intermediate frame sectionW4, and a filter F22 which has the opening O of for example, 70 μm fromthe intermediate frame section W4 to the intermediate frame section W5,and a filter F23 which has the opening O of for example 30 μm betweenthe intermediate frame section W5 and the frame section W2. By this, itbecomes easier to constitute the filter so as to make the opening Ofiner in the step-by-step way. As well as in this case, it is possibleto avoid the dust to be stuck to the frame sections W3-W5 by providingeach filter F21-F23 to inner surface of the frame sections W3,W4 and W5.

As mentioned above, according to the electric vacuum cleaner in thepresent invention, it is possible to improve the separating efficiencyby separating the dust and the air efficiently.

[Mode for Carrying Out the Invention 6]

FIGS. 20-23 show an electric vacuum cleaner corresponding to the thirdembodiment of the present invention. The same reference numbersindicated in FIGS. 1-8 are given for the parts identical or resembles tothe structure of the embodiment shown in FIGS. 1-8, and theirdescriptions are omitted.

In the motor-driven section 34 of the main body case 30, a battery 39 isloaded at a down side of the motor fan 33 as shown in FIG. 20. Thebattery 39 provides electric power to the motor fan 33. Additionally, itis possible to provide the electric power of a commercial alternatingcurrent to the motor fan 33 or the like through a cord reel bysubstituting the battery 39 shown in the figure with the cord reel andarranging the cord reel at the same part.

As shown in FIG. 20 and FIG. 21, the container case body 53 has the dustcollection room section (dust accumulating section) 55 which is formedat a lower part of the case body 53, the negative pressure room section(negative pressure space) 56 formed mainly at an upper part of the dustcollection room section 55, a first dust separation section 60 providedat inside of the negative pressure room section 56, and the strikesection 63 as a guiding section which is leading the dust separated bythe dust separation section 60 to the dust collection room section 55.

The bottom face of the dust collection room section 55 is opened. Thebottom plate 57 is attached to the bottom part of the dust collectionroom section 55 capable of opening and closing in about the axis J, andit is possible to dispose the dust accumulated in the dust collectionroom section 55 by opening the bottom plate 57. The closed state of thebottom plate 57 is adapted to be released through a mechanism which isnot shown in the figure that is operated simultaneously by the press-inoperation of a control button provided on the handle section 54. 74denotes a circular shaped seal which is fixed at an inner surface of thebottom plate 57 and thereby air tightness at a lower end part of thedust collection room section 55 is provided when the bottom plate 57 isin closed condition.

The suction opening 52 is formed at an upper part of the front wall 53 aof the dust collection case 50 as an opening for a sucking use. Also,the dust collection case 50 has a rear side wall (first wall) 55A of thedust collection room section 55 near to the rear part of the opening 51,and the top panel (second wall) 58 which is continuously bent from theupper end of the rear side wall 55A to the front wall 53 a. The toppanel 58 and the rear side wall 55A divide the lower part's dustcollection room section 55 and the upper part's negative pressure roomsection 56. At the top panel 58 which constitutes a ceiling wall of thedust collection room section 55, the ventilation opening 59 is formedthat communicates the dust collection room section 55 with the negativepressure room section 56.

The ventilation opening 59 is provided such that the ventilation opening59 substantially faces a center of the dust collection room section 55.By this, the ventilation opening 59 faces to the filter F2 of the firstdust separation section 60 which will be described later from a lowerpart of it. The filter F1 which is made from a net for example and whichis attached to the ventilation opening 59.

The mesh of the filter F1 is 30 μm-110 μm, preferably 60 μm-80 μm. Bythe filter F1, it is possible to avoid the dust which has more size thanpredetermined size to flow into the negative pressure room section 56,as well as facilitating the maintenance for removing the dust clogged atthe filter F1.

The connection hole 58A is formed at the side of the wall 60 a of thetop panel 58. At lower part of the connection hole 58A, there isprovided the guide wall G to generate spiral flow at inside of the dustcollection room section 55.

The first dust separation section 60 constitutes an inertia separationdevice which is in a direct advancing flow type for separating the airand the dust by inertia-separation effect, and has the tubular filter 62which forms the tubular passage 61 as a separation air passage, and hasthe strike section (guiding section) 63.

The tubular filter 62 as an air passage body has the tubular frame Wwhich is for example, in a hollow cone shape in which one end and another end are both opened and has the plurality of openings (separationopening) 64 as the air guiding opening at its entire circumference in aregular interval, and has the filter F2 for blocking the openings 64 ofthe tubular frame W. To say in detail, the tubular frame W, the tubularfilter 62, is constituted by a small and large pair of round framesections W1 and W2 and the plurality of ribs W3 which connect the framesections W1 and W2. The respective openings 64 are formed by spacessurrounded by the both frame sections W1, W2 and W3. The filter F2 ismade by the net for example, and is attached along the inner peripherysurface of aforementioned frame in a tubular shape.

Therefore, the tubular filter 62 constitutes a structure as if bothsides in an axial direction of a mound are opened, and the tubularshaped passage 61 is formed which is surrounded by the tubular filter62. It is recommendable to provide aforementioned ventilation opening 59at least near to the small diameter part of the tubular filter 62 in afacing manner.

This tubular shaped passage 61 extends linearly to the axial direction(to the longitudinal direction in the present embodiment) of the vacuumcleaner main body 20. The tubular shaped passage 61 is communicated withthe intake opening 33A of the motor fan 33 subsequently through theopenings 64 of the tubular filter 62, the negative pressure room section56 of the container case body 53 and the opening 34A of the motor-drivensection 34 of the main body case 30.

The diameter of the one end opening 62A which is a large diameter of thetubular filter 62 is formed larger than the diameter of the suctionopening 52 of the container case body 53. The tubular filter 62 isconnected to the container case body 53 so that the suction opening 52falls within the one end opening 62A. The diameter of the other endopening 62B which is a small diameter of the tubular filter 62 is formedvirtually the same diameter of the suction opening 52. By this, thediameter of the tubular filter 62 is gradually decreasing as going fromthe one end to other end linearly. By the way, it may be recommendablethat the diameter of the other end opening 62B of the tubular filter 62is smaller than the diameter of the suction opening 52.

An axis line of the tubular filter 62 and an axis line of the connectionpipe 44 of the lid body 40 continue virtually in alignment, and theintake opening 33A of the motor fan 33 is provided in such a manner asto face on these extending axes. The connection pipe 44 of the lid body40, the suction opening 52 of the container case body 53, the tubularfilter 62, the opening 51 of the container case body 55 and the intakeopening 33A of the motor fan 33 are subsequently arranged along theaxial direction (the longitudinal direction in the present embodiment)of the vacuum cleaner main body 20 at virtually the same heightposition.

The strike section 63 is provided continuously at the other end opening62B of the tubular filter 62. To say in detail, the strike section 63has the slant wall section 63A extending from the upper side of theother end opening 62B of the tubular filter 62 to the lower side on aslant, and the strike wall section 63B (wind striking wall section)which faces to the other end opening 62B of the tubular filter 62 and isalso incurved from the one end of the slant wall section 63A andextending to the lower part, and the side wall section 63C which isformed at both sides of the slant wall section 63A and the strike wallsection 63B. Additionally, the strike section 63 has the opening 63Dwhich is jointed to the other end opening 62B of the tubular filter 62.

A lower part of the strike section 63 constitutes a tubular shape andwhich is for example, extending in a vertical direction and covering theconnection hole 58A, and is also connected throughout the ceiling wall58 and the uprising wall 60 a. By this connection, the strike section 63communicates the tubular shaped passage 61 with the dust collection roomsection 55.

This uprising wall 60 a is provided slightly inside (front side) thanthe opening 51 of the container case body 53, and giving a predetermineddepth H to the opening 51. The filter 80 which constitutes the seconddust separation section is attachably and detachably loaded inside ofthe opening 51 by using the depth H (see FIGS. 20, 21 and 23).

The filter 80 is provided with a filter frame 81 and a filter element 82which is loaded in such a manner as to block entire inner side of theframe 81. The filter element 82 is constituted by making the filtermedium in a mat shape, and particularly in the present embodiment, apleat-shaped filter element is used which the pleat process is appliedfor expanding the filter element 82 in a thickness direction thereof.The mesh of this filter element 82 is finer than the mesh of filters F1and F2 which are at a former step.

Next, an operation of the electric vacuum cleaner constituted as abovewill be described.

As mentioned above, by actuating the motor fan 33, the partial airsucked to the tubular shaped passage 61 is sucked by the negativepressure room section 56 of the container case body 53 through the firstfilter F2 of the openings 64 of the tubular filter 62, and furthersucked by the intake opening 33A of the motor fan 33 through the filter80 which is loaded on the opening 51 of the container case body 53.

In this sucking of the air, the dust which has more weight than apredetermined weight and which is sucked to the tubular shaped passage61 that extends straight in a longitudinal direction of the vacuumcleaner main body 20 cannot be passed through the openings 64 bychanging its direction suddenly because of its inertia. Consequently,aforementioned dust which has weight is adapted to be separated from theair that passes the openings 64, and goes straight through the tubularshaped passage 61, and then hits to the strike wall section 63B of theguiding section 63 and is introduced into the dust collection roomsection 55 along the strike section 63.

Some of the air is adapted to be introduced into the dust collectionroom section 55 through the strike section 63 as similar toaforementioned dust which has the more weight. The introduced air asjust stated then becomes spiral flow by the guide wall G in a downwarddirection which revolves along the inner peripheral surface of the dustcollection room section 55. Consequently, the dust introduced into thedust collection room section 55 is adapted to be accumulated as it iscompressed along the lower inner peripheral surface of the dustcollection room section 55 by aforementioned spiral flow.

The air turned into the spiral flow by being introduced inside of thedust collection room section 55 is reversed and drifted upward at acenter part in the dust collection room section 55, and goes through theventilation opening 59 of the dust collection room section 55 and issucked by the negative pressure room section 56 of the container casebody 53, and further goes through the filter 80 which is loaded on theopening 51 of the container case body 53 and is sucked by the intakeopening 33A of the motor fan 33.

In this case, since the ventilation opening 59 is provided at the wall58 in such a manner as to face virtually the center part of the dustcollection room section 55, it is less likely that the dust within thedust collection room section 55 attaches to the filter F1 of theventilation opening 59. Moreover, the air sucked to the intake opening33A from the dust collection room section 55 through the ventilationopening 59 flows the negative pressure room section 56 via outerperipheral surface of the filter F2 which is in a hollow cone shape by apositional relationship between the ventilation opening 59 and the dustseparation section 60, or to be more precise, the air flows the negativepressure room section 56 while blowing the filter F2 from the lowerdirection of the filter F2.

At the same time, because the light weighted dust flows with the airthat goes through the filter F2 of the openings 64 by an intake negativepressure of the motor fan 33 without going straight through the tubularshaped passage 61 which is in the tubular filter 62 of the dustseparation section 60, the dust becomes attached to the inner peripheralsurface of filter F2. If the clogging of the filter F2 caused by theattachment of the light weighted dust becomes larger, the amount of windthat goes through the filter F2 reduces. But the negative pressure ofthe negative pressure room section 56 increases corresponding to theamount it reduced as well as the negative pressure within the dustcollection room section 55 through the ventilation opening 59 of thefirst wall 58. Consequently, the wind velocity and the amount of wind ofthe air that goes straight through the tubular shaped passage 61increase.

As stated above, even if the amount of wind that passes through thefilter F2 is reduced by clogging, the amount of wind the motor fan 33sucks can be maintained substantially constant because the amount ofwind goes straight through the passage 61 increases. Therefore, it isalways possible to suck the dust by the predetermined sucking power withirrespective of the clogging of the filter F2.

Moreover, if the wind velocity that goes straight through the tubularshaped passage 61 becomes larger as above mentioned, the air that goesstraight becomes easier to peel off the dust attached to the filter F2.On this occasion, because the diameter of the tubular shaped air passagebody 62 gradually decreases as going from the upstream side's opening62A to the downstream side's opening 62B, the air that goes straightthrough the tubular shaped passage 61 hits equally to entire surfaces ofthe filter F2 and flows as gravitated toward the center part of thetubular shaped passage 61. Therefore the air becomes easier to peel offthe dust attached to the inner surface of the filter F2.

In addition, because the air trying to reach the intake opening 33A ofthe motor fan 33 from the dust collection room section 55 through theventilation opening 59 hits the outer peripheral surface of the filterF2 as already mentioned, the air becomes easier to peel off the dustattached to the inner surface of the filter F2.

To say in detail, because the dust attached to the inner surface of thefilter F2 is influenced by a force pulling toward an outside directionby the negative pressure caused by the negative pressure room section 56and a transferring force caused by the air passing the tubular shapedpassage 61, particularly a relatively long dust and a membranous dustwhich became equivalent to a relatively long condition substantially bya development of the attachment to the inner surface of the filter F2,are easier to stop at its current position while maintaining an unstableattached condition at the inner surface of the filter F2 by anantagonism of aforementioned two forces. If there is retention of thedust at the inner surface of the filter F2 as such, the dust attachmentdevelops easily from there as a center. In addition, the velocity of thedust contained air that tries to penetrate the hollow cone shaped filterF2 in a longitudinal direction becomes slow as going to a side of thesmall diameter part of the tubular filter 62 which the filter F2 isattached to the inner peripheral surface, therefore the dust attacheseasily to the inner surface of it.

However, since the force trying to pull the dust attached to the innersurface of the filter F2 by the negative pressure of the negativepressure room section 56 can be weakened in that area where the air hitsby the air hitting the outside of the filter F2, a superiority inaforementioned transferring force can be made by breaking a balance ofaforementioned forces. By this, the dust attached to the inner surfaceof filter F2 can be peeled off easily even more. In addition, becausethe ventilation opening 59 faces to the small diameter part of thetubular filter 62 and the air hits at least outside of the side of thesmall diameter part of the filter F2, it is possible to remove the dustattached to an inner surface of the small diameter part effectively.

In addition to this, in the area where the air hits outside of thefilter F2, since the force trying to pull the air in the filter F2outside by the negative pressure of the negative pressure room section56 can be weakened, it is possible to reduce and restrain the attachmentof the dust to aforementioned area.

Furthermore, since it is structured that the air passed the ventilationopening 59 hits from the lower part of the filter F2, even if it is thedust that is attached to the lower part of the inner surface of thefilter F2, it is possible to peel off effectively as already mentioned.

The dust that is peeled off from the inner surface of the filter F2 asstated above is adapted to be introduced into the dust collection roomsection 55 through the strike section 63 as similar to the heavyweighted dust, and is separated from the air centrifugally in the dustcollection room section 55 and is accumulated.

In addition, in the dust separation room section 60, because the dust isseparated from the air by using the inertia force caused by the heavyweighted dust such as coarse dust trying to move forward rather thanswirling the dust contained air and centrifugally separating the dustand the air while reversing the moving direction of the spiral flow, theloss of air passage becomes less in the dust separation section 60.Moreover, because the suction opening 52, the separation air passage 62a, the opening 51 of container case body 53 and the intake opening 33Aof the motor fan 33 are virtually at the same height position and arearranged in order continuously in the longitudinal direction, the mainflow of the air does not change significantly as shown representativelyby the arrow Q in FIG. 3, and flows substantially straight forward atalmost the same height position when the air is sucked to the negativepressure room section 56 of the container case body 53 through thefilter F2 from the tubular shaped passage 61, and is sucked by the motorfan 33.

Consequently, the loss of air passage becomes even less, which theperformance of the motor fan 33 can be achieved sufficiently.Furthermore, because the connection pipe 44 of the lid body 40 and thetubular shaped tubular filter 62 are arranged in a straight line, thedirection of the air introduced to the suction opening 52 of thecontainer case body 53 and the extending direction of the tubular filter62 become substantially in alignment, therefore its loss of air passagebecomes even more less.

As mentioned, because the air inside of the negative pressure roomsection 56 passes the filter 80 and sucked by the motor fan 33, themicroscopic dust passed the filters F1 and F2 can be captured by thefilter 80, and the motor fan 33 can suck the cleaned air cleaned bythem.

Furthermore, in the cleaning operation as described above, at anupstream side of the filter 80 which is for separating the dust by thepercolation, the dust separation section 60 which is for separating thedust by the inertia separating effect is arranged, so that the coarsedust or the like is separated at the dust separation section 61beforehand. By this, it is possible to avoid the filter 80 to be as anapparent clogged condition at an early stage due to the attachment ofthe large dust at the filter 80 that is supposed to be removed at thedust separation section 60.

The present invention is not limited by aforementioned one embodiment.For example, it may be also recommendable to provide the tubular filter62 in a straight pipe shape such as a circular cylinder or an angularpipe, and the filter F1 of the aforementioned one embodiment can beomitted, and in the dust collection room section 55, it is also possibleto omit the guide wall G which is for creating the spiral flow. Inaddition, the filter 80 which constitutes the second dust separationsection in aforementioned one embodiment can also be detachablysustained at the main body case 30 and can be fixed into the opening 51which is provided at the container case body 53 of the dust collectioncase 50 in connection with attaching the dust collection case 50 to themain body case 30.

As described above, according to the present invention, it is possibleto provide the electric vacuum cleaner in which the loss of air passagecan be reduced compared with the one that carries out the cyclone typeseparation, and the deterioration in the amount of wind can besuppressed easily even if the dust accumulates at the dust separationsection.

[Mode for Carrying Out the Invention 6]

FIGS. 24 and 25 show an electric vacuum cleaner corresponding to thesixth embodiment of the present invention. The same reference numbersindicated in FIGS. 1-8 are given for the parts identical or resembles tothe structure of the embodiment shown in FIGS. 1-8, and theirdescriptions are omitted.

In the sixth embodiment of the present invention, it is constituted thatwhen the wind velocity going straight of the passage 61 of the tubularfilter 62 increases, the air going straight through the passage peelsoff the dust attached to the net filter F2. On this occasion, as anangle α between a peripheral wall 62S and a center line L of the tubularfilter 62 is set virtually 30 degrees, the wind going straight throughthe passage 61 hits the entire surface of the net filter F2 equally, andthe wind becomes easier to flow along the surface of the net filter F2,consequently the dust attached to the net filter F2 becomes easier to bepeeled off.

Next, operation on the electric vacuum cleaner constituted as abovementioned will be described hereunder.

By actuating the motor fan 33 in such a manner as mentioned above, theair sucked to the passage 61 is adapted to be sucked by the negativepressure room section 56 of the container case body 53 through the netfilter F2 of the openings 64 of the tubular filter 62, and is furthersucked by the intake opening 33A of the motor fan 33 through the filter80 which is loaded on the opening 51 of the container case body 53.

Meanwhile, because the passage 61 extends linearly to the longitudinaldirection, the dust which is sucked to the passage 61 of the tubularfilter 62 and which has more weight than predetermined weight goesstraight through the passage 61 by the inertia and is introduced insideof the dust collection room section 55 by the guide pipe 70. That is tosay, the dust and the air are separated by the dust separation section60.

Also, some of the air is adapted to be introduced inside of the dustcollection room section 55 through the guide pipe 70, and the introducedair then turns into spiral flow by the guide wall G of the dustcollection room section 55, and the dust introduced inside of the dustcollection room section 55 is accumulated by the spiral flow as it iscompressed.

The air that is introduced into the dust collection room section 55 is,when it is turned into spiral flow, sucked into the negative pressureroom section 56 of the container case body 53 through the ventilationopening 59 of the top panel 58 of the dust collection room section 55.

As the light weighted microscopic dust flows with the air that goesthrough the net filter F2 of the openings 64 without going straightthrough the passage 61 of the tubular filter 62, the dust becomesattached to the net filter F2. Although the amount of wind that goesthrough the net filter F2 reduces by the attachment of the microscopicdust to the net filter F2, the negative pressure of the negativepressure room section 56 of the container case body 53 increasescorresponding to the amount it reduced as well as the negative pressurewithin the dust collection room section 55 through the ventilationopening 59 of the top panel 58. Consequently, the wind velocity of theair that goes straight through the passage 61 of the tubular filter 62becomes greater, therefore the amount of wind going straight increases.

When the wind velocity that goes straight through the passage 61 of thetubular filter 62 become greater, the air that goes straight peels offthe dust attached to the net filter 62. On this occasion, as the angle αbetween the peripheral wall 62S and the center line L of the tubularfilter 62 is set virtually 30 degrees, the wind going straight throughthe passage 61 hits the entire surfaces of the net filter F2 equally,and the wind becomes easier to flow along the surface of the net filterF2, consequently the dust attached to the net filter F2 becomes easierto be peeled off.

By the way, if the degrees of the angle α between the peripheral wall62S of the tubular filter 62 and the center line L of the tubular filter62 becomes larger, the amount of dust attaching the net filter F2increases because the amount of wind Q hitting the net filter F2 equallyincreases as shown in FIG. 25. Also, the amount of wind Q′ flowing alongthe net filter F2 as shown by the chained line decreases. Consequently,the attached dust becomes harder to be peeled off from the net filter F2by the wind Q′, only the amount of dust attaching to the net filter F2increases.

But when the angle α becomes less than 45 degrees, the amount of dustthat attaches to the net filter F2 can be decreased because of theamount of wind Q hitting equally to the net filter F2 decreases, andfurthermore, because the amount of wind Q′ flowing along the net filterF2 increases, it becomes preferable that the wind Q′ becomes peeling offthe dust attached to the net filter efficiently.

If the angle α becomes too small, the amount of dust attaching to thenet filter F2 decreases significantly because the amount of wind Qhitting equally to the net filter F2 decreases significantly, but theamount of wind Q hitting equally to the net filter F2 becomes subtle,therefore the amount of wind Q′ flowing along the net filter F2decreases significantly. Consequently, the dust attached to the netfilter F2 becomes harder to be peeled off by the wind Q′.

Therefore, when the angle α is at virtually 30 degrees, it is possibleto reduce the amount of dust attached to the net filter F2 as well asincrease the amount of wind Q′ that is flowing along the net filter F2,thereby it becomes most preferable that the dust attached to the netfilter F2 can be peeled off in most effective manner.

The peeled dust is then introduced and accumulated inside of the dustcollection room section 55 through the guide pipe 70.

According to the invention as described above, even if the dust attachesto the net filter, the attached dust can be removed efficiently by theair that flows in the air passage.

[Mode for Carrying Out the Invention 7]

FIGS. 26-33 show an electric vacuum cleaner corresponding to the seventhembodiment of the present invention. The same reference numbers used inabove mentioned embodiment of the invention are given for the partsidentical or resembles to the structure of the above mentionedembodiment of the invention, and their descriptions are omitted.

In FIG. 26, 20 is the vacuum cleaner main body, and the one end of thehose 21 is connected attachabley and detachably to the vacuum cleanermain body 20 and the hand operating pipe 22 is provided on its otherend. The extension pipe 23 is connected attachably and detachably to thehand operating pipe 22 and the suction opening body 24 is connected tothe end of the extension pipe 23 attachably and detachably. Also, thecontrol section 22A is provided on the hand operating pipe 22, and thereis provided on the control section 22A the control switch which is notshown.

As shown in FIGS. 27 to 29, the vacuum cleaner main body 20 is comprisedof the main body case 30 and a dust collection case (dust cup) 50 whichis attachably and detachably mounted on the main body case 30 and thelid body 40 capable of opening and closing in a vertical direction withthe back end of the lid body 40 being connected to the main body case 30by the hinge connection.

The main body case 30 has a cord reel room 36 which is formed at a lowerpart and installed with a cord reel CR and has the motor-driven room 34which is loaded with the motor fan 33 and formed above the cord reelroom 36. At front side of the cord reel room 36, there is provided themounting section 35 which is in the plate shape that protrudes to theforward direction. Onto the mounting section 35 the dust collection case50 is attachably and detachably mounted. Furthermore, the dustcollection case 50 is adapted to be fixed by a hold of the lid body 40and the mounting section 35 when the lid body 40 is closed.

Also, the front side of the motor-driven section 34 of the main bodycase 30 is made opened, and this opening 34A faces and is communicatedwith the intake opening (intake vent) 33A of the motor fan 33. At bothside faces of the main body case 30, the plurality of exhaust holes 38are formed. These exhaust holes 38 are communicated with the exhaustopening 33B of the motor fan 33 through the exhaust air passage which isnot shown, and the air exhausted from the exhaust opening 33B of themotor fan 33 is exhausted outside from the exhaust holes 38 through theexhaust air passage.

To the lid body 40, the connection pipe 44 which has the connectionopening 43 at the front end of the connection pipe 44 which isattachably and detachably connecting the dust collection hose 21, isprovided. The connection pipe 44 is extended in a longitudinal directionand its rear end has an opening 45A.

As shown in FIG. 30 to FIG. 32, the dust collection case 50 has theopening 51 on the rear face (right side in FIG. 31) and a case body 53which has a front side opening (case opening) 50 a at the front face,and the handle section 54 which is integrally formed at the case body53.

The case body 53 has the dust collection room section (dust collectionsection) 55 formed at the lower part, the negative pressure room section56 formed at above the dust collection room section 55, the dustseparation section 60 provided within the negative pressure room section56 and the guide pipe 70 for guiding the dust separated at the dustseparation section 60 to the dust collection room section 55.

The front side opening 50 a of the case body 53 is closed by means of anopening and closing lid 90. On a back of the opening and closing lid 90,a seal member 91 is fixed which attaches to a peripheral part of itsfront side opening 50 a. The seal member 91 seals between the front sideopening 50 a and the opening and closing lid 90.

To the opening and closing lid 90, a communicating pipe 92 is providedwhich is communicated with the connection pipe 44 of the lid body 40,and an opening 92A which is located at a front end of the communicatingpipe (suction opening) 92 is jointed with the opening 45A of theconnection pipe 44, and the communicating pipe 92 is communicated withthe passage 61 of the dust separation section 60 through the front sideopening 50 a. Above the opening and closing lid 90, a pair of arms 93(only one is shown) are provided extending in a backward direction(rightward direction in FIG. 30), and an axis P is provided at end ofthe arms 93 that extends in right and left direction (the directionperpendicular to a page space in FIG. 33). The axis P is rotatably fixedto an upper part of the case body 53.

In addition, the opening and closing lid 90 opens the front side opening50 a of the case body 53 by rotating about the axis P as a center asshown in FIG. 33. In other words, the opening and closing lid 90operates the opening and closing movement by rotating about the axis Pas the center.

[Operation]

Next, an operation of the electric vacuum cleaner constituted as abovewill be described hereinafter.

First, as shown in FIG. 29, the dust collection case 50 is mounted onthe mounting section 35 of the main body case 30 and the lid body 40 isclosed, and the hose 21 is connected to the connection opening 43 of thelid body 40. When operating the switch of the control section 22A whichis not shown, the motor fan 23 actuates. By the actuation of the motorfan 23, the negative pressure room section 56 of the case body 53becomes negative pressure through the openings 34A of the main body case30. This negative pressure acts upon the openings 64 of the tubularfilter 62, the passage 61 of the tubular filter 62, the front sideopening 50 a of the case body 53, the communicating pipe 92 of theopening and closing lid 90, the connection pipe 44 of the lid body 40,the hose 21, the extension pipe 23 and the suction opening body 24,thereby the dust is sucked together with the air from the suctionopening body 24.

The sucked dust and air are sucked toward the connection opening 43 ofthe lid body 40 through the extension pipe 23 and the hose 21. The dustand the air that are sucked to the connection opening 43 are suckedtoward the passage 61 of the tubular filter 62 of the dust separationsection 60 through the connection pipe 44 of the lid body 40, thecommunicating pipe 92 of the opening and closing lid 90 and the frontside opening 50 a of the case body 53.

When cleaning the dust attached to the net filter F2 of the dustseparation section 60, first, the lid body 40 is opened as shown in FIG.28 and the dust collection case 50 is dismounted from the mountingsection 35 of the main body case 30. Then, the opening and closing lid90 of the case body 53 of the dust collection case 50 is opened and thefront side opening 50 a of the case body 53 is opened as shown incross-section in FIG. 33. By this opening operation, it is possible toput fingers or the like from its front side opening 50 a so that thedust attached to the net filter F2 can be rubbed off by the fingers orthe like, therefore the cleaning of the net filter F2 becomes ever soeasy. Furthermore, it can be cleaned even more if the whole dustcollection case 50 is wet-cleaned. Like so, the cleaning of the netfilter of the dust separation section becomes very easy to be cleaned.

As described above, the electric vacuum cleaner according to theembodiment of the present invention, the dust separation section 60 isprovided at the suction air passage which is leading from the suctionopening (connection opening 43 or suction opening 52, suction opening100) of the vacuum cleaner main body 20 to the intake opening (33A,107A) of the motor fan (33, 107) to separate the dust sucked from thesuction opening (connection opening 43 or suction opening 52, suctionopening 100) with the air and the dust collection section (dustcollection room section 55, dust collection room 104) provided at thesuction air passage for collecting the dust separated from the air atthe dust separation section 60.

In addition, the dust separation section 60 of this electric vacuumcleaner has the tubular passage (passage 61) which the one endcommunicates with the suction opening (connection opening 43 or suctionopening 52, suction opening 100) so that the dust sucked from thesuction opening (connection opening 43 or suction opening 52, suctionopening 100) flows in and the other end communicates with the dustcollection section (dust collection room section 55, dust collectionroom 104), and the air guiding opening (openings 64, openings 102H)provided at the peripheral wall of the tubular passage (passage 61) andis communicated with the intake opening (33A, 107A) of the motor fan(33, 107).

Generally in the conventional electric vacuum cleaner with the cyclonesystem, because the air swirls round and then reversed and driftedupward and sucked, the loss of air passage of the air is large (i.e.,loss in an amount of air passing through is large). Also in theconventional electric vacuum cleaner with the paper package as the paperfilter, when the predetermined amount of dust is accumulated in thepaper package, the amount of air decreases easily. On the contrary, inthe electric vacuum cleaner of the present embodiment, as the dustsucked with the air goes straight by inertia and is collected, and theair is sucked by the motor fan (33, 107) through the air guiding opening(openings 64, openings 102H), the air and the dust are separated withoutgenerating spiral flow, therefore the loss of air passage becomes less.

Also, the electric vacuum cleaner according to the embodiment of thepresent invention, the dust separation section 60 is provided at thesuction air passage leading from the suction opening (connection opening43 or suction opening 52, suction opening 100) of the vacuum cleanermain body 20 to the intake opening (33A, 107A) of the motor fan (33,107) to separate the dust sucked from the suction opening (connectionopening 43 or suction opening 52, suction opening 100) with the air andthe dust collection section (dust collection room section 55, dustcollection room 104) provided at the suction air passage for collectingthe dust separated from the air at the dust separation section 60.

Moreover, the dust separation section 60 of this electric vacuum cleanerhas a dust guiding duct adapted to inflow the dust sucked from thesuction opening (connection opening 43 or suction opening 52, suctionopening 100) from the one end and for guiding the dust flows in from theother end to the dust collection section by the inertia force, and anair guiding air passage is provided to be communicated with themidstream of the dust guiding duct and is communicated with the intakeopening (64, 102H) of the motor fan (33, 107) without passing throughthe dust collection section.

As well as in the electric vacuum cleaner of the present embodiment, asthe dust sucked with the air goes straight by inertia and is collected,and the air is sucked by the motor fan (33, 107) through the air guidingopening (openings 64, openings 102H), the air and the dust are separatedwithout generating spiral flow, therefore the loss of air passagebecomes less.

Also, the electric vacuum cleaner according to the embodiment of thepresent invention, the dust separation section 60 is provided at thesuction air passage which is leading from the suction opening(connection opening 43 or suction opening 52, suction opening 100) ofthe vacuum cleaner main body 20 to the intake opening (33A, 107A) of themotor fan (33, 107) to separate the dust sucked from the suction opening(connection opening 43 or suction opening 52, suction opening 100) withthe air and the dust collection section (dust collection room section55, dust collection room 104) provided at the suction air passage forcollecting the dust separated from the air at the dust separationsection 60.

Moreover, the dust separation section 60 of this electric vacuum cleanerhas the tubular passage (passage 61) which the one end is communicatedwith the suction opening (connection opening 43 or suction opening 52,suction opening 100) and adapted to flow in the dust sucked from thesuction opening (connection opening 43 or suction opening 52, suctionopening 100), and an air guiding air passage provided at the one endwith the air guiding opening (openings 64, openings 102H) which isprovided on the peripheral wall of the tubular passage (passage 61) andthe other end is communicated with the intake opening (openings 64,openings 102H) of the motor fan (33, 107) without passing through thedust collection section (dust collection room section 55, dustcollection room 104).

As well as in the electric vacuum cleaner of the present embodiment, asthe dust sucked with the air goes straight by inertia and is collected,and the air is sucked by the motor fan (33, 107) through the air guidingopening (openings 64, openings 102H), the air and the dust are separatedwithout generating spiral flow, therefore the loss of air passagebecomes less.

Also, the electric vacuum cleaner according to the embodiment of thepresent invention, the dust strike section (63, 103) which is providedat the other end side of the tubular passage (passage 61) and isprovided for hitting the dust that flows into the tubular passage(passage 61) and goes straight through it, and the dust collectionsection (dust collection room section 55, dust collection room 104) forcollecting the dust being hit to the dust strike section (63, 103) isprovided at a lower part of the strike section 63.

As well as in the electric vacuum cleaner of the present embodiment, asthe dust sucked with the air goes straight by and is collected, and theair is sucked by the motor fan (33, 107) through the air guiding opening(openings 64, openings 102H), the air and the dust are separated withoutgenerating spiral flow, therefore the loss of air passage becomes less.Furthermore, the dust does not fly up within the dust collection section(dust collection room section 55, dust collection room 104).

Also, the air guiding opening (openings 64, 102H) of the electric vacuumcleaner according to the embodiment of the present invention is providedthroughout the entire circumference of the peripheral wall of thetubular passage (passage 61).

As well as in the electric vacuum cleaner of the present embodiment, asthe dust sucked with the air goes straight by the inertia and iscollected, and the air is sucked by the motor fan (33, 107) through theair guiding opening (openings 64, openings 102H), the air and the dustare separated without generating spiral flow, therefore the loss of airpassage becomes less.

Also, a filter is provided at the air guiding opening (openings 64,102H) of the tubular passage (passage 61) of the electric vacuum cleaneraccording to embodiment of the present invention. According to thisstructure, because the light weighted dust (microscopic dust) does notgo straight (difficult to be influenced by the inertia) to the duststrike section (strike section 63) by the inertia force caused whensucked into the tubular passage (passage 61) is sucked to the side ofthe motor fan 33 with the air through the air guiding opening (openings64, openings 102H), it is possible to capture the light weighted dust atthis occasion using the filter.

Also, the tubular passage (passage 61) of the electric vacuum cleaneraccording to the embodiment of the present invention is provided withthe filter tube section (net filter F2) as a tubular shaped filter inthe mesh shape which is located at the upstream side, and a tube section(frame section W2) which is continuously built to the downstream side ofthe filter tube section and has non-permeability. According to thisstructure, although the light weighted microscopic dust that isdifficult to be influenced by inertia is captured by the filter tubesection (net filter F2) at the upstream side, it is hard to break intothe mesh of filter (net filter F2) and it is easier to be peeled off. Inaddition, the dust influenced by inertia hits to the non-permeabilitytube section (frame section W2) at the downstream side since it iseasier to go straight, so the dust influenced by inertia does not clogthe filter (net filter F2).

Also, the filter (net filter F2) of the electric vacuum cleaner in theembodiment of the present invention is in the mesh shape, and theopening O of the mesh shape filter (net filter F2) is formed finer asgoing from the upstream side to the down stream side of the tubularpassage. According to this structure, because the dust is easier to gostraight since the wind velocity at the upstream side is fast, thepermeability is increased at the upstream side by having the opening Oof the mesh shape filter (net filter F2) to be wider, therefore it ispossible to increase the sucking efficiency. Furthermore, at thedownstream side of the tubular passage (passage 61), because the openingO of the filter (net filter F2) is fine, the flow of air becomes smooth,therefore clogging of the filter (net filter F2) can be avoided.

Also, the filter (net filter F2) of the electric vacuum cleaneraccording to the embodiment of the present invention is in the meshshape, and the surface finishing for reducing the friction resistance isapplied on the filter (net filter F2). According to this structure, thedust is hard to be attached to the filter (net filter F2) since thesurface finishing for reducing the friction resistance is applied on thefilter (net filter F2).

Also, the diameter of the tubular passage (passage 61) of the electricvacuum cleaner according to the embodiment of the present invention isgradually decreased from the one end to the other end directionlinearly. According to this structure, the air (wind) going straightbecomes easier to hit equally the entire surfaces of the air guidingopening (openings 64) which is provided at the peripheral wall of thetubular passage (passage 61), therefore the dust attached to the filter(net filter F2) is easily peeled off.

Also, the diameter of the one end opening 62A of the tubular passage(passage 61) of the electric vacuum cleaner according to the embodimentof the present invention is larger than the diameter of the suctionopening 52 of the vacuum cleaner main body, and the diameter of theother end opening 62B of the tubular passage is less than the diameterof the suction opening 52 of the vacuum cleaner main body. According tothis structure, the air (wind) going straight becomes easier to hitequally the entire surface of the air guiding opening (openings 64)which is provided at the peripheral wall of the tubular passage (passage61), therefore the dust attached to the filter (net filter F2) is easilybe peeled off.

Also, the vacuum cleaner main body 20 of the electric vacuum cleaneraccording to the embodiment of the present invention is provided withthe dust collection case 50 which has the dust separation section 60 andthe dust collection section 60. Furthermore, the tubular passage(passage 61) of the dust separation section 60 is formed inside of thetubular filter 62 which is for separating the dust sucked from thesuction opening (communicating pipe 92) of the vacuum cleaner main body20, a diameter of a filter entrance opening of the tubular filter 62 isformed larger than the diameter of the suction opening (communicatingpipe 92) of the vacuum cleaner main body 20, the case opening (frontside opening 50 a) which faces to the filter entrance opening isprovided at the dust collection case 50, the opening and closing lid 90for blocking the case opening (front side opening 50 a) is providedcapable of opening and closing, and the suction opening of the vacuumcleaner main body 20 is provided at the opening and closing lid 90.

According to this structure, the fingers or the like are difficult toput into the suction opening of the vacuum cleaner main body 20,therefore by providing the side of the suction opening as being capableof opening and closing, it is easy to carry out the cleaning since theuser can easily remove the dust attached to the tubular filter 62.

Also, the dust collection case 50 of the electric vacuum cleaneraccording to the embodiment of the present invention is providedattachably and detachably to the vacuum cleaner main body 20. Accordingto this structure, it is easy to carry out the cleaning since the wholedust collection case 50 can be wet-cleaned.

Also, the electric vacuum cleaner according to the embodiment of thepresent invention, the intake opening 33A of the motor fan 33 isprovided to suck some of the air that flows into the tubular passage(air passage 61) through the dust collection section (dust collectionroom section 55) by communicating the dust collection section (the dustcollection room section 55) with the air guiding air passage (negativepressure room section 56) and by communicating the dust collectionsection (dust collection room section 55) with the intake opening 33A ofthe motor fan 33.

According to this structure, when the filter is clogged by theattachment of the dust to the filter (net filter F2), a flowing speed ofthe air to the dust collection section (dust collection room section 55)becomes faster and the dust attached to the filter (net filter F2) ispeeled off, therefore the clogging of the filter (net filter F2) can besolved.

Also, the electric vacuum cleaner according to the embodiment of thepresent invention, the ventilation opening 59 which exhausts some of theair guided from the dust strike section (strike section 63) to the dustcollection section (dust collection room section 55) with the dust tothe air guiding air passage (negative pressure room section 56) bycommunicating the dust collection section (dust collection room section55) with the air guiding air passage (negative pressure room section 56)is provided at a wall (top panel 58) which forms and divides the dustcollection section (dust collection room section 55).

According to this structure, it is possible to contribute to adownsizing of the vacuum cleaner main body 20 since it is possible toguide the remaining air that flows into the dust collection section(dust collection room section 55) to the intake opening 33A of the motorfan 33 by utilizing the air guiding air passage (negative pressure roomsection 56) which guides some of the air from the air guiding opening(openings 64) provided at the tubular passage (passage 61) directly tothe intake opening 33A of the motor fan 33 so as to maintain adirect-advancing element.

Also, the electric vacuum cleaner according to the embodiment of thepresent invention, the dimension of the ventilation opening 59 of thedust collection section (dust collection room section 55) is smallerthan the dimension of the air guiding opening (openings 64) of thetubular passage (passage 61). According to this structure, it ispossible to increase the dust separation efficiency in the tubularpassage (passage 61) by increasing the amount of air which flows fromthe air guiding opening (openings 64) of the tubular passage (passage61) directly to the intake opening 33A of the motor fan 33 (i.e.,maintaining a direct-advancing element) than the amount of air flowingto the dust collection section (dust collection room section 55).

Also, the electric vacuum cleaner according to the embodiment of thepresent invention, the first filter (net filter F2) is attached to theair guiding opening (openings 64) of the tubular passage (passage 61).According to this structure, when the first filter (net filter F2)clogs, the wind amount of air that passes through the air guidingopening (openings 64) reduces and the negative pressure at the airguiding air passage (negative pressure room section 56) increases. Whenthe negative pressure at the air guiding air passage (negative pressureroom section 56) increases, the negative pressure within the dustcollection section (dust collection room section 55) becomes largerthrough the ventilation opening 59, and the wind velocity of air goingstraight of the tubular passage (passage 61) becomes faster, so that aclogged situation of the first filter (net filter F2) can be avoidedsince the dust attached to the first filter (net filter F2) can bepeeled off, therefore it is possible to avoid the deterioration in thesucking efficiency.

Also, the electric vacuum cleaner according to the embodiment of thepresent invention, the dust collection section (dust collection roomsection 55) is provided at a down side position of the dust separationsection 60, the ventilation opening 59 is provided at an upper wall (toppanel 58) of the dust collection section (dust collection room section55), and the second filter (net filter F1) is attached to theventilation opening 59. According to this structure, as the ventilationopening 59 is provided in a vertical direction, it is possible to fallthe dust attached to the second filter (net filter F1) by its ownweight, therefore it is possible to remove the dust from the secondfilter (net filter F1) easily.

Also, the electric vacuum cleaner according to the embodiment of thepresent invention, the ventilation opening 59 is provided so that theair exhausted from the dust collection section (dust collection roomsection 55) hits the first filter (net filter F2). According to thisstructure, it becomes easier to peel off the dust attached to the innersurface of the first filter (net filter F2).

INDUSTRIAL APPLICABILITY

As described above, in the dust separation structure of the electricvacuum cleaner relating the present invention, it is structured that therelatively heavy dust sucked with the air is adapted to go straight byusing inertia force, and separate the air from the dust which is movingstraight at a part where the dust is moving forward and suck by themotor fan. The dust separation structure as such can be utilized inordinary household-use electric vacuum cleaner (including the ones whichthe power is supplied by a battery or a cord), an upright type electricvacuum cleaner or a commercial-use electric vacuum cleaner or the like.

1. An electric vacuum cleaner comprising: a dust separation sectionprovided at a suction air passage between a suction opening of a vacuumcleaner main body and an intake opening of a motor fan to separate dustsucked from the suction opening with air; a dust collection sectionprovided at the suction air passage for collecting the dust separatedfrom the air at the dust separation section; a tubular passage which iscommunicated at a first end with the suction opening to flow in the dustsucked from the suction opening; an air guiding air passage having anair guiding opening on a peripheral wall of the tubular passage to guideair from the air guiding opening to the intake opening of the motor fanwithout passing through the dust collection section; and a dust strikesection which is provided at a second end of the tubular passage,wherein the dust that flows into and through the tubular passage hitsthe dust strike section, wherein the dust collection section is providedat a lower part of the dust strike section for collecting the dust whichhas hit the dust strike section, and wherein a filter is provided at theair guiding opening of the tubular passage, and a diameter of thetubular passage gradually decreases linearly from the first end to thesecond end.
 2. The electric vacuum cleaner according to claim 1, whereinthe air guiding opening is provided throughout an entire circumferenceof the peripheral wall of the tubular passage.
 3. The electric vacuumcleaner according to claim 1, wherein the tubular passage has: (i) afilter tube section which comprises a tubular shaped filter having amesh shape and which is located at an upstream side, and (ii) a tubesection which is continuously built to a downstream side of the filtertube section and which is not permeable.
 4. The electric vacuum cleaneraccording to claim 1, wherein the filter has a mesh shape, and openingsof the mesh shape filter are formed finer from an upstream side to adownstream side of the tubular passage.
 5. The electric vacuum cleaneraccording to claim 1, wherein the filter has a mesh shape, and a surfacefinishing for reducing friction is applied to the filter.
 6. Theelectric vacuum cleaner according to claim 1, wherein a diameter of thefirst end of the tubular passage is larger than a diameter of thesuction opening of the vacuum cleaner main body, and a diameter of thesecond end of the tubular passage is less than the diameter of thesuction opening of the vacuum cleaner main body.
 7. The electric vacuumcleaner according to claim 1, wherein the vacuum cleaner main bodycomprises: a dust collection case which comprises the dust separationsection and the dust collection section; a tubular filter whichseparates the dust sucked from the suction opening of the vacuum cleanermain body, wherein the tubular passage is formed inside of the tubularfilter, and a diameter of a filter entrance opening of the tubularfilter is larger than a diameter of the suction opening of the vacuumcleaner main body; a case opening which faces the filter entranceopening, and which is provided at the dust collection case; an openingand closing lid for opening and closing the case opening, wherein thesuction opening of the vacuum cleaner main body is provided at theopening and closing lid.
 8. The electric vacuum cleaner according toclaim 7, wherein said the dust collection case is provided detachablyattached to the vacuum cleaner main body.
 9. The electric vacuum cleaneraccording to claim 1, wherein the intake opening of the motor fan suckssome of the air that flows into the tubular passage through the dustcollection section by communicating the dust collection section with theair guiding air passage so as to communicate the dust collection sectionwith the intake opening of the motor fan.
 10. The electric vacuumcleaner according to claim 9, further comprising: a ventilation openingwhich is provided at a wall which forms and divides the dust collectionsection, wherein the ventilation opening exhausts some of the air guidedfrom the dust strike section to the dust collection section with thedust to the air guiding air passage by communicating the dust collectionsection with the air guiding air passage.
 11. The electric vacuumcleaner according to claim 10, wherein a dimension of the ventilationopening of the dust collection section is smaller than a dimension ofthe air guiding opening of the tubular passage.
 12. The electric vacuumcleaner according to claim 10, wherein: the dust collection section isprovided at a lower side position of the dust separation section; theventilation opening is provided at an upper wall of the dust collectionsection; and a second filter is attached to the ventilation opening. 13.The electric vacuum cleaner according to claim 10, wherein theventilation opening is provided substantially directly underneath thefilter which is provided at the air guiding opening of the tubularpassage so that the air that exhausts from the dust collection sectionhits the filter.